Rechargeable and disposable batteries – the environmental impact

September 4th, 2013.

First published July 2008, last updated September 2013

I wouldn’t call myself a gadget freak, but in my work and given I spend a good deal of time away from a mains power supply, I use a lot of battery powered equipment. I started using rechargeables some years back and it’s definitely saved me a lot of cash.

But what about the environment?

I guess it’s a bit of a no-brainer that if you use one of something compared to a zillion, it’s got to be  better for the planet, but not if the one of something is one zillion and one times toxic :). So I decided to take a look at how rechargeable batteries stack up against their disposable counterparts.

Disposable and rechargeable battery types

Disposable, or dry-cell batteries are usually the alkaline type. They used to contain very high levels of mercury, but the amounts used have greatly decreased over the last couple of decades and some brands use none at all. Still, some do contain a small amount of mercury and given the massive waste involved should be avoided, or at the very least, recycled.

While rechargeable batteries have dropped in price over the years, the love affair with disposables continues. According to figures from Japan’s Ministry of Economy, Trade and Industry; in June 2013, over 75 million alkaline batteries were produced. This was a massive increase of 96% year over year.

Unfortunately, it can be difficult finding places that will actually recycle disposable alkaline batteries. Many recyclers separate them from rechargeables and they wind up in landfill anyway.

A service I came across in the USA for alkaline (and rechargeable) battery recycling is Big Green Box, which is just a box you can dump batteries into and when it’s full, send it back to the recycler. You can purchase a box for your home or office, or utilize one that’s in one of the participating stores mentioned on their site.

Button batteries are a problem as a great deal of metal is used for their comparatively small size and they can contain mercury, silver, cadmium, lithium, or other heavy metals as their main component. Thankfully, due to the increasing price of raw materials, these are a desired recyclable item.

Rechargeable batteries used to be quite environmentally toxic beasties, containing cadmium (NiCad batteries). These days, one of the more common AA and AAA rechargeables are Nickel-metal-hydride (NiMH). NiMH batteries have a better life and performance than Nicads and don’t contain as much in the way of toxic heavy metals, so they are a “greener” choice.

If you own a notebook, it’s likely the battery in it is Lithium-ion. These are the top of the line in terms of performance and the type we’re seeing in electric cars. Again, these are a more environmentally friendly option than NiCads.

Here’s a bit of rechargeable battery trivia: – the Tesla Roadster’s battery pack isn’t one big battery or even a few – it uses 6,831 18650 Lithium-ion batteries!


You can also buy rechargeable alkaline batteries, but these perform poorly and will cost you more in the long run – and you’ll create more waste.

Regardless of the lower environmental toxicity of today’s rechargeable batteries, they should definitely be recycled rather than thrown in the bin to wind up in landfill.

Where to recycle rechargeable batteries

If you’re in the USA or Canada, try Call2Recycle, the Rechargeable Battery Recycling Corporation (RBRC) program’s web site for further information. The following is a short video about Call2Recycle’s operations.

In Australia, Battery World stores offer a free service that has collected over 6,000 tonnes of used batteries so far.

In the UK, there’s a free recycling program called BatteryBack – the initiative aims to have over 50,000 collection points by the end of 2013

Environmental savings

According to a study by Uniross carried out in 2007, the production of rechargeable batteries has the following advantages over disposables (comparing serviceable life):

– 23 times less potential impact on non-renewable natural resources
– 28 times less potential impact on global warming
– 30 times less potential impact on air pollution (ozone pollution)
– 9 times less potential impact on air acidification
– 2 times less potential impact on water pollution

Getting the most from rechargeable batteries

I made a few mistakes using rechargeable batteries in the beginning, so I offer the following tips so you might avoid the same. These simple tips will help ensure you get the maximum life from your rechargeables.

– If you’re going to buy rechargeables – keep track of them :). Being small critters, batteries are easier to lose. Given that a rechargeable battery in itself is more toxic to the environment than a single disposable alkaline; if you keep losing them and keep buying more, it defeats the purpose. Have a central point in the house or your car where you store flat ones. I also mark each battery set (eg. mb1, mb2, mb3, mb4) so there’s equal ‘wear’, rather than mixing old ones with new ones.

– Avoid using the batteries at high temperatures and store out of direct sunlight

– Recharge regularly

– Avoid overcharging.

Cost savings

As mentioned, you can not only lighten your environmental footprint, but save a ton of cash by using rechargeable batteries.

A pack of 4 rechargeable batteries I purchased a short while ago cost me around $20. They’ll be good for at least 500 recharges, likely more. A battery charger costs anywhere from about $10 -$30. The cost to recharge the set works out to be just a couple of cents each time; even factoring in electricity. So, in total, even taking into account in the charger, a set of 4 AA will cost no more than $55 for their serviceable life.

A comparable set of heavy duty disposables cost around $2 – and that’s at a discount price. The equivalent usage would cost $1000!

Environmentally and financially, rechargeable batteries just make more sense. If you can, try ditching your disposable battery habit and reap the rewards.

Natural Gas And The Environment

August 18th, 2013.

First published June 2010, last updated August 2013

With the tide (thankfully) starting to turn against coal fired power generation, renewable energy is finding favor, as is electricity generated via the combustion of natural gas.

So, is natural gas green?

What is natural gas?

Natural gas consists mainly of methane and is often found associated with oil fields, coal seams and other fossil fuel deposits; but also may exist on its own in huge underground reservoirs.

Extraction methods

Like oil, natural gas is often obtained through targeted drilling, however at times it’s a by-product of oil drilling. Not so long ago, gas associated with oil extraction was simply burned off (flaring), but now it’s increasingly captured for use.

In drilling operations where natural gas is targeted, hydraulic fracturing may also be employed once a well is sunk to the required depth to boost the flow of gas. The fracture is formed by pumping special fluid into the base of the well. This process is also known as “fracking”.

Natural gas processing

While natural gas will burn without refining; in order to make it suitable for residential, automotive and industrial use, it must be processed – and that in itself is an energy intensive task. However, the by-products of the process produces useful substances such as propane and butane.

Natural gas emissions

Natural gas is often referred to as the “cleanest” of the fossil fuels, including so-called “clean coal“. According to, the burning of natural gas emits almost 30 percent less carbon dioxide than oil, and just under 45 percent less carbon dioxide than coal.

However, this isn’t the full story – burning gas may create lower emissions, but the entire production process can be emissions intensive. A major issue is fugitive emissions from gas that escapes during extraction. In a medium case scenario, life-cycle emissions per joule of energy derived from fracked gas could potentially be similar to those derived from coal.

While the combustion of natural gas also results in lower levels of nitrogen oxides (which contribute to acid rain), sulfur, carbon monoxide, and virtually no particulate matter; it’s this lack of particulate matter compared to coal combustion that may mean a shift to gas could accelerate a rise in global average temperatures. Confused? I don’t blame you. Read more about this aspect here.

CNG (Compressed Natural Gas) and automobiles

CNG is becoming an increasingly popular alternate fuel for cars. says the EPA has found vehicles using compressed natural gas have reductions in carbon monoxide emissions of up to 97 percent, carbon dioxide emission reductions of 25 percent and nitrogen oxide emission reductions of up to 60 percent.

Natural gas environmental implications

Natural gas certainly sounds like a panacea for all society’s energy woes in some ways – but it is a fossil fuel and unlike solar power and like oil, it is a limited resource. As such, a massive switch to natural gas would see many of the problems associated with oil production still occur.

The fugitive emissions risk aside, extraction of natural gas can be an environmentally damaging process. The process of “fracking” involves toxic waste and can contaminate the ground water with the fluids and the gas itself. In some parts of the world, the amount of natural gas that has leaked into aquifers through nearby fracking activities is enough to burn – I’ve seen photos of people lighting their faucets.

Fracking operations can also draw heavily on groundwater and are believed to be connected with some earthquake incidents.

The hydraulic fluids themselves can be somewhat of a black box, with some in the industry refusing to reveal the components of the fluids involved. The documentary “Gasland” claims some fluids contain known carcinogens and heavy metals.

Gas produced from fracking operations is “wet” and needs to be separated from the water and fracking fluid when it comes to the surface and this wastewater can also be highly toxic.

In some countries, land owners may own the surface area of their properties, but not the resources that lay beneath. Some are forced to allow gas drilling operations on their property and there’s little recourse if the company involved doesn’t restore the land to what it was before. The same problems can occur on government or public land; as with all forms of mining.

As mentioned, another environmental issue is the methane itself. While methane does burn quite cleanly, it is a very potent greenhouse gas – around 60 times the Greenhouse Warming Potential (GWP) of carbon dioxide. Methane leaks from extraction and during transportation just add to an already greenhouse gas overburdened atmosphere.

A great deal of energy is required to process natural gas and while some by-products of that process are useful, others are just toxic waste, such as hydrogen sulfide and carbonyl sulphide

While natural gas may be “greener” than all other fossil fuels (and that is certainly debatable as more information becomes available), it’s certainly not green – it’s the lesser of the fossil fuel sourced energy evils.

Natural gas provides an interim source of energy while we wean ourselves off coal and oil and perhaps as a baseload source of energy when needed; but there’s a danger of  natural gas being seen as a replacement for renewable energy for our future power needs.

Natural gas will not solve the climate change issue – it should be seen only as part of the solution and a stepping stone to even cleaner energy technology.

Seasonal Energy Storage

July 12th, 2013.

Seasonal Energy Storage is a fancy term relating to something humanity has been doing for a very long time – burning wood and other biomass.

As we shift away from fossil fuels more towards renewable energy; the intermittent nature of these resources means energy storage is the next holy grail. There’s been so much progress in this area; but more needs to be made before we can transition to 100% renewables.

I’ve never viewed a lump of wood as an energy storage device; but I guess it is. Wood and other forms of biomass could play an important role in a renewable energy system with wind and solar power as the centerpiece.

So how much storage would the USA need to back up wind and solar-centric power generation system? Between 7% and 26% of total electricity demand it seems.

And where would all this biomass come from? It would take a lot of land to grow the biomass and we’ve wrecked so much of that already.

That is where part of the answer may lie – abandoned croplands. I had no idea so much existed in the USA. According to a recent study, there’s around 71 million hectares of it. 71 million hectares is approximately 274,133 square miles; larger than the state of Texas.

What form would that biomass take? Rather than trees, switchgrass is one possibility. Not only can it be burned much the same way as coal, it can also be used in liquid fuel production (e.g. ethanol and butanol), and synthetic gases.

Switchgrass is already being used in some facilities in combination with coal; which reduces power plant emissions. Special burners have also been designed to burn it specifically.

I can’t say I’m really keen on burning anything to create power; it seems to me to be just the same old, same old; but I’m not familiar with new technologies or how clean they are.

I’m also not aware of how energy or resource intensive cultivating something like switchgrass would be, but it’s a US native and apparently quite hardy. There are other biofuel crops that can also be grown on marginal lands.

Personally, I’d love to see that fallow 71 million hectares returned to its natural state; but that’s a bit of a pipe dream.

Still, it’s great to see all sorts of alternatives to the black death (coal) appearing and a renewable energy future becoming more of a reality each day. Energy storage of this nature doesn’t need to be an either/or situation either – many different technologies will likely be used.

You can view the study, “Seasonal energy storage using bioenergy production from abandoned croplands” here.


Wood heaters and efficiency

Air conditioner choices and tips for staying cool inside

July 3rd, 2013.

First published June 2009, last updated July 2013

While it’s winter here in Australia, in the northern hemisphere it’s summer and things have been really heating up in some countries. At the time of updating this article, it’s 3am in Las Vegas and the temperature there is 37C (98F). At 3am!

A few days back Las Vegas experienced temperatures of 47C (129F) and in Death Valley, the mercury climbed to 54C (129F).

Even by Australian standards, that is incredibly hot.

Unfortunately, most houses haven’t been constructed, insulated or positioned correctly in order to minimize the amount of artificial air conditioning required to keep temperatures indoors bearable throughout the summer months. Add to this the urban heat island effect and things can become very uncomfortable and even life threatening.

This will become an increasing challenge in the years ahead as global warming really starts to kick in and developing nations start having increased access to luxuries, or in some cases necessities, such as air conditioning. Millions more people will start using air conditioners and for longer periods.

Aside from the spike in electricity and water consumption connected to air conditioner usage that costs consumers and the environment a great deal, utility company transformers are well known to overheat and explode when air conditioning usage hits its peak during a heatwave, often cause massive blackouts and fires. The use of air conditioners also adds to the urban heat island effect.

Basic tips for staying cools indoors

Where I live is pretty much a desert state – it’s not unusual for temperatures here to hit above 100 degrees Fahrenheit (38 degrees Celsius) for days on end during summer. When we moved into our previous house, we were very surprised to find that the roof wasn’t insulated – at all.

Dark roof tiles and summer heat aren’t a really good combination; so instead of running the air conditioner for many hours a day, we invested in earth friendly roof insulation made from recycled cellulose fiber. It was a great investment, not only keeping us cooler during summer, but warmer during winter and increasing the value of our house. Additionally, it helped to reduce noise from outside.

But even with that insulation in place, the house still became quite hot at times – unfortunately it was built facing east-west instead of north-south as it should in the southern hemisphere to take advantage of passive solar warming during the winter months and present a side of the house to the sun with fewer windows during the summer.

To further reduce the need for air conditioning, over the summer we leave some doors and windows of the house that have security screens on them open from the evening through to early in the morning to let out pent up heat. We then shut the house up and draw the curtains as the temperature rises. When temperatures indoors get to the stage that it’s uncomfortable, then the air conditioner goes on – usually not until well after midday on the hottest days of the year.

Here are some other tips for staying cooler indoors without air conditioning:

– The use of ceiling and pedestal fans. While a fan on its own doesn’t reduce temperature, the movement of air over your skin evaporates perspiration causing a cooling effect – making the temperature feel up to 8 degrees cooler. You don’t need to be sitting directly in front of the fan to feel some benefit – it’s just a matter of getting air inside the room moving. If you decide to install a ceiling fan, try to buy one that has a reverse feature – it can then be useful in winter too.

– Gaps around doors and windows should be sealed to prevent hot air entering the house. Again, this will be of benefit during winter too.

– All electrical appliances generate heat; especially refrigerators and some TV’s. Plasma screens in particular are known to create a great deal of heat, to the point that some refer to them as space heaters.

If you’re not watching the TV, switch it off. Encourage your family not to have the refrigerator door open for extended periods and don’t overload your fridge. Turn off any appliance at the wall you’re not using (this will also reduce standby power consumption)

– Switch from incandescent bulbs to LED or Compact Fluorescent Lamps (CFL’s) as 80% – 90% of the energy consumed by incandescent lighting is wasted through heat. CFL’s will also save you money in electricity.

– Try to confine physical activity such as housework to the early hours of the day or late in the evening.

– Try to prepare foods that require the least amount of cooking as possible and use a microwave where you can. Ensure your range hood exhaust fan is switched on while cooking.

– Wear clothing that breathes, such as cotton. Avoid wearing shoes as our feet are also designed to be efficient heat exchangers. In fact, the less clothing you can get away with, the better as our bodies have quite an effective inbuilt cooling system.

– Curtains and shades should be a light color and of heavy material to help reflect/block the heat. Blackout curtains can also help keep heat in during winter.

– Keep rooms you don’t use often closed off.

– Plant trees around your house to provide a shade buffer between the sun and your walls. Use deciduous trees on the northern or southern side (depending on the hemisphere you live in) so you can still take advantage of passive solar warming in winter.

– Discourage your family from coming in and out of the house excessively. Each time the door is opened, a substantial blast of hot air will follow.

– Drink plenty of fluids, but steer clear of alcohol and sugar laden drinks.

– A spray bottle full of water kept close at hand can be a great way to get a bit of relief, particularly if there’s some air movement.

– A damp cloth applied to the back of the neck can help take the edge off the heat

Don’t forget about your pets.

Dogs don’t perspire, but cool themselves by panting. If your dog is panting rapidly and salivating heavily, this could be a sign of heat stress.

Make sure your pets have plenty of water and in the case of dogs, a spray every once in a while with a spray bottle containing water or a shallow tub with a few inches of water in it that the dog can stand in can be a big help.

Niki the Wonder Dog enjoying some respite during a heatwave
when temperatures reached as high as 48.5C (119F)!

After seeing the difference the tub idea made to the comfort of Niki the Wonder Dog, I tried it out myself and yes, it does really work. Even though only my toes were covered with water, it had a fantastic overall cooling effect. A minute or so standing in the tub and I’m good to continue enduring the 40+ degree celsius (105F +) temperatures we regularly experience for a while in a better frame of mind .

It does get to a stage in some parts of the world where the above simply won’t be enough. If you are considering buying an air conditioner, there are three types commonly used in homes:

Evaporative air conditioning

These units are also known as air, swamp or desert coolers and range in size from portable units suitable for single rooms to massive installations that can cope with entire complexes.

Rooftop evaporative air conditioners use a fan that draws in air through a wet filter. As the hot air passes through the filter (usually made of paper or straw), the water evaporates which cools and humidifies the air. Depending on temperature and external humidity, evaporative air coolers can reduce indoor temperatures by as much as 30° F (17° C).

Evaporative air conditioning isn’t a new invention – as mentioned above, nature has installed evaporative cooler in our own bodies in the form of perspiration. Artificial evaporative air conditioning was invented thousands of years ago in Iran. In its simplest form, a wind shaft in the roof of a dwelling would channel air over a small pond of water, cooling the air before being blown into the house. The Iranians had far more complex and efficient installations as well that still rival any modern electrical cooling appliance in terms of effectiveness.

Evaporative coolers are best suited to environments such as ours – they are incredibly effective in dry air climates. An evaporative cooler used in a humid environment will be totally ineffective and likely make discomfort even worse.

One of the great aspects of evaporative air conditioning is maintenance and running cost – up to 80% less than other forms of artificial air cooling. An evaporative air cooler is usually around 50% cheaper to purchase also. A negative aspect of evaporative air conditioning is water usage – around 3.5 gallons per hour for a ducted system on the average home; but refrigerated air conditioning also involves the use of water indirectly through increased electricity consumption.

If you find that only a single room in your home really needs air conditioning, small mobile evaporative cooling units can be purchased for under a hundred dollars.

Important tip: Evaporative air conditioning works best when you leave a couple of doors or large windows open – the cooling effect is dependent upon air turning over within a house. By running evaporative air conditioning with the house entirely shut up, you will increase humidity to uncomfortable levels and this can also cause issues with mold and electrical equipment malfunctions.

It may sound odd having a door open when it’s 115 outside, but as long as the door or window left open is on the opposite side of external air movement and not in direct sunlight, heat from outside will not enter – the air pressure from inside will keep it out. If you have an outdoors barbecue area or pergola attached to the house, it’s a great way to keep that a tad cooler too!

Refrigerated air conditioning

This type works very much the same way as your refrigerator, using the evaporation of a refrigerant liquid in a closed system to provide cooling. A compressor compresses the gas, which heats it. The gas then passes through coils allowing the heat to dissipate and for the gas to condense into a pressurized liquid. The pressurised liquid then passes through an expansion valve where it it hits a low pressure area due to the vacuum action of the compressor at the other end of the line. It then becomes a gas again at a much lower temperature, cooling the pipe that contains it. This gas flows through an insulated line to to a console unit containing a series of coils with a fan behind it; which sucks air from the room over the coils (unless it is a split system, then air is drawn from outside), cooling the air and then pushing it back into your home.

Refrigerated air conditioning also removes humidity from the air through the condensation of moisture on the cold evaporator coils. This condensate is drawn away to either evaporate in a pan over the warm condenser coils or just run directly outside.

While refrigerated air conditioning doesn’t directly use water, it does use a great deal more electricity than evaporative air cooling. That’s where the water usage lies; in the electricity generation process. When this is taken into account, the amount of water used by refrigerated cooling unit is approximately two thirds that of an evaporative unit.

The use of inverters in refrigerated air conditioning has delivered some energy savings – I’ve read claims of between 30 and 50 percent. Air conditioners without inverters need to stop and start in order to maintain a room’s temperature, whereas models featuring inverters automatically adjust the compressor speed.


Not as common for cooling applications as refrigerated or evaporative air conditioning, dehumidifiers are sometimes used in tropical locations to remove moisture from the air – a major contributor to a feeling of discomfort in higher temperatures. In a dehumidifier system, moisture laden air is drawn over a coil, much like a refrigerated air conditioner’s evaporator coils. Moisture from the air condenses on the coils, then drips into a pan or is piped into a drain. The air then moves over another warmer coil and is then blown back into the room.

While the resulting air isn’t really cooled, with the excess moisture removed it makes higher temperatures more tolerable. Dehumidifiers are used in situations where humidity is too high for an evaporative cooler, but refrigerated cooling cannot be used. The amount of electricity consumed is about half that of a comparable refrigerated air conditioning unit.

Air conditioners and off grid living

If you’re living off the mains grid and have limited access to water and power, it can be difficult to find a suitable air conditioner. I looked for many months for a unit I could use while in the bush and running off a small mobile solar power system. I finally stumbled across the MightyKool, a very portable personal evaporative air conditioner made in the USA. I’ve had it for a few seasons now and it’s absolutely brilliant. It only uses about a quart of water an hour and draws just .8 amps at its lowest setting. While it’s not a cheap item, it’s been worth every penny as there have been a few occasions where this powerful little air conditioner has likely prevented me from suffering heat stroke.

Artificial air conditioning – luxury or necessity?

The human race survived relatively well before air conditioning was powered by electricity and complex manufactured systems. The arrival of modem artificial cooling is somewhat a blessing and a curse due to the large amounts of energy required to run these systems – we need to use it wisely and see it as a luxury and privilege when it’s not being used in critical situations.

If you do run an air conditioner, before switching the cool on, try just running the fan for while until things really start heating up – it can save substantial energy and water. Also remember that the aim is to stay cool so you can function, not to create a refrigerator type environment – experiment with thermostat settings and find the highest possible temperature before you start feeling too uncomfortable.

I’ve noticed some houses in my neighborhood run their air conditioning units 24/7 over much of summer; but don’t bother closing curtains or taking other low/no-cost steps to minimize heat entering into their homes. It’s annoying to hear the hum of all the motors of a night time – more noise pollution – and the practice consumes an incredible amount of electricity.

While there are certainly situations where air-conditioning is a matter of life and death, I think we all need to toughen up just a bit when it comes to our expectations of acceptable living comfort levels. The planet depends upon us doing so.

Energy Efficiency – tips for saving electricity

May 30th, 2013.

(First published May 2009, last updated May 2013)

While solar power and wind energy offer us a greener future when it comes to power generation, the cleanest watt is the one that doesn’t have to be generated.

Energy efficiency is the low hanging fruit of greenhouse gas reduction. By taking a little care with how we use electricity in our homes, we not only lighten the load on the environment, but we can save cash too.

In many parts of the world, the cost of electricity is rapidly increasing due to a variety of factors. One of the reasons is demand – as we acquire more power sucking gadgets and gizmos; this not only means more electricity needs to be generated, but additional infrastructure must be built for transmission and distribution.

Regardless of the reasons for electricity price increases; there are many ways to cut the costs of your power bill – and some changes will cost you nothing to implement or very little.

Electricity saving example: computers

I’m writing this by the light of a 1 watt LED lamp and on my laptop with power saving features switched on – using around 50 watts maximum. Back some years ago, I would have been basking under the light of a 100 watt incandescent globe and using a desktop computer with a 17″ CRT screen – around 300 watts all told.

So what do those savings come to in terms of carbon emissions?

The following are some rough calculations based on coal fired power generation for just the computer aspect:

Laptop = 50w x 10 hours a day x 365 days = 182.5 kilowatt hours
Desktop = 300w x 10 hours a day  x 365 = 1095 kilowatt hours

A huge difference as you can see and in terms of carbon emissions, the savings by using a laptop are around 1360 pounds annually – well over half a ton.

In the case of coal fired electricity, each kilowatt you save not only puts cash back into your pockets, but also avoids up to 1.5 pounds of carbon dioxide emissions being generated; not to mention all the other environmentally nasty stuff associated with power generation.

So there’s the first tip. If you use a desktop computer, when it does come time to buy another computer; consider a notebook instead. If you’re not ready to acquire another computer, there are other tips below you can use with your current system.

The following are brief tips on how you can save electricity in the home and in the office. Click the links for more energy saving information and other green tips associated with each topic.

Get expert advice – free.

Many governments now offer household energy efficiency programs that are free to participate in. These programs may consist of free kits containing information and energy saving devices or may involve a qualified assessor visiting your home who will offer you advice specific to your situation. Contact your local government or electricity authority to determine what’s on offer.


Tumble dryers are massive energy suckers, but if you need to use them, ensure the lint filter is clean and the room where the clothes dryer is has plenty of air circulation. This will allow your clothes to dry faster and save electricity; as will ensuring that they’ve gone through a fast spin in your washing machine. Of course, line dry wherever possible.

In regard to washing machines, the biggest energy savings can be made in relation to water temperature. Given today’s detergents, hot water doesn’t really need to be used for the average load; cold water will work just fine. Also experiment with your machine to see how short a cycle you can use and still achieve effective results.


If you have an electric stove, always select the right pan for the job and for the hot plate size.

When needing to boil water for cooking, it’s likely more efficient to boil it in your kettle or microwave instead of on an oven hot plate.

Many kitchens have both a microwave and a stove, so wherever possible use your microwave for cooking items as they can use a third to half the electricity of a stove.

Ensure your oven light is working and the inspection glass is clean –  significant heat will be lost if you have to open the door to check on your food.

When cooking on a stove or a range top; you can switch it off just before your food is done. There will be enough heat to finish the cooking.

When boiling the kettle for a cup of coffee or tea, only have as much water as you need in the kettle. This not only saves energy, but will get your morning fix to you much quicker :).

Check your refrigerator to ensure the seal is in good condition as even small gaps can affect performance dramatically. Your fridge should also be situated out of direct sunlight and placed in such away to allow for good air circulation; particularly at the back. If yours is an old fridge, the coils at the back should be regularly dusted.

Regularly defrosting your fridge and freezer will also help to conserve electricity. Also change the settings on your fridge and freezer to take into account the season – it can usually be switched to a higher (warmer) setting during winter.

Unplug kitchen appliances when not in use as many of these will consume standby power.

Heating and air conditioning

By sealing up gaps around your home, using earth friendly insulation and blackout curtains, you can dramatically decrease the amount of electricity you use in heating and cooling your home. The use of ceiling fans and roof turbines can also provide benefits in both winter and summer.

Whether you’re heating or cooling your home, keep the doors shut to rooms that don’t require it.

During winter, try wearing a little more clothing as it may allow you to drop the thermostat a little. Similarly, wearing less clothing over summer will allow you to perhaps raise the thermostat so your air conditioner doesn’t have to work so hard. A degree or two either way can make a huge difference over a season.

Also ensure your heater and air conditioning system is regularly serviced as required – this will help keep it performing at its maximum efficiency.

Depending on your domestic situation and location, something else you can consider for the cooler months is task-based heating – for example, using a heating pad. Warm feet can go a long way to making the rest of you feel warm. Heating pads can be particularly useful if you work in a home-based office. I’ve been using one for a while now and I expect to save 60-70% on my winter heating bills.

Hot water

Heating water is one of the most energy intensive applications in the home.

If you have an electric water heater, consider adding a heater blanket to help insulate it further – these are quite cheap and can pay for themselves very quickly. Additionally, check the lagging around exposed pipes and replace if necessary.

Get your family to co-operate also by taking shorter showers. Gauging how long you’ve been in the shower for can be quite difficult as space and time become warped in a shower I’ve found – I tend to zone out :). You can buy waterproof hourglass and digital shower timers as a visual (and sometimes audible) reminder.

If your water heater is on its last legs, consider a switch to a gas heater, or even better, a solar hot water system or heat pump. The new generation of solar heaters are extremely efficient, work well in winter and usually have a gas or electric heating backup in case of extended unfavorable weather. Additionally, renewable energy rebates may make these systems comparable in price to traditional systems.


The obvious – only leave lights switched on when you need them.

Incandescent globes are miniature heaters – most of the energy used by a traditional light bulb is converted to heat rather than light. CFL (Compact Fluorescent Lamps) use far less electricity and LED lamps even less. While more expensive than traditional light globes, they also last far longer.

Dimmer switches can also help you save electricity in the home, but if you’re using CFL or LED lamps, make sure they are compatible with dimming features.

Also consider task-based lighting. For example, when working on the computer at night, I don’t need to have the whole room bathed in light, just my computer desk area; so I use an LED lamp that draws only a watt.

If you use lighting outdoors consider solar powered garden lamps. These usually require no wiring as they have internal rechargeable batteries and will switch on automatically at dusk and switch off at dawn. For security lighting, use sensor lights that will only switch on when someone approaches.

A responsible approach to exterior lighting not only saves electricity but also reduces light pollution.


As mentioned, switching from a desktop machine to a notebook is a great way to save electricity. However, even with a desktop system there’s a lot you can do to green your computer use.

When you’re not using your computer for extended periods, switch your computer off at the wall to avoid phantom power load consumption.

Ensure your power saving/management options are enabled and properly configured. In Windows, this can be found in Settings/Control Panel/Power Options

While using your computer, only have your screen as bright as you need it – unnecessarily bright screens will use additional electricity.

For a screen saver, use a blank (black) screen as animated screen savers are energy suckers.

Replacing appliances

Thankfully, appliance manufacturers are realizing that the age of cheap energy is over and are increasingly making products that are more energy efficient.

For example, new refrigerators are far more energy efficient that the ones of 20 years ago. Today’s air conditioners can use up to 50% less electricity than those of 20 years ago. Front loading washing machines have dropped a great deal in price recently and are also more energy efficient that top loaders.

However, when buying new appliances, do check their energy ratings as they can still vary widely.

If particularly environmentally conscious, you should also weigh up if getting rid of an old appliance that’s functioning perfectly for the sake of saving electricity is worth it in comparison to the resources used in making a new appliance. At the very least, don’t dump the old appliance, repurpose it (refrigerators make for great storage spaces!) or give it away to someone who may be able to use it.

Mantra – save a kilowatt, save a pound.

As mentioned, in the case of coal fired electricity generation, a kilowatt saved is over one pound of carbon emissions not generated; so each kilowatt does count when it comes to lessening our environmental impact, particularly when millions of people are making an effort. The real cost of coal in terms of the environment is so much more than just carbon emissions too.

Here’s an easy way to remember it – save a kilowatt, save a pound!

Portable evaporative air conditioner – MightyKool

May 7th, 2013.

First published September 2009, last updated May 2013

One of the big challenges of off grid living in a hot area is cooling – both food and yourself. It’s not just a matter of being water and energy efficient for the sake of the environment, but often due to the limitations of resources available.

On my little patch of outback Australia, I was able to tackle the food cooling issues to a degree with an electricity-free Zeer pot. However, in the summer of 2008, Niki the Wonder Dog and I learned that air conditioning sometimes isn’t a luxury, but a real necessity.

I usually love the heat, but when native animals adapted to living in dry, hot conditions started started dying from heat stress; even with water available to them, that’s when I realised I might be in trouble.

We got through the worst days that summer using a few old techniques for keeping cool indoors, but only just and it was terribly uncomfortable at times. One day it reached 48C (118F) inside and there were many days of 40C+ (104F+).

Given I only had a small mobile solar power rig (single 130 watt panel) to run my notebook 12 hours+ a day and some lighting; I didn’t have a lot of capacity to spare for power assisted cooling. Refrigerated air conditioning was definitely out of the question and even evaporative air conditioners are mostly rated at 150 watts +.

I started to design a small personal evaporative air conditioner; but I’m no designer. Even in my head, it looked like something out of the Flintstones.

I searched for solutions around the world off and on for months and found nothing that was compact, light on electricity and water consumption. Then I came across MightyKool, a product from USA company Swampy Cooling Systems who have been making 12 volt portable cooling systems since 1989.

What follows is going to sound like an ad for the MightyKool, but I assure you I paid full price for my unit. It’s just that I’ve been so impressed with the Mighty Kool as it does *exactly* what I need it to and I can see it being very useful to not only folks living off grid, but for use on camping trips as well.

Here’s what my unit looks like – also to give you an idea of the size (please excuse the pinkish tinge – the unit is white). Looking at the Swampy Cooling Systems site, there appears to have been some cosmetic updates since I purchased mine:

MightyKool personal evaporative air conditioner

It’s small, but very powerful; able to crank out over 200 cubic feet of air per minute.

The first thing I want to mention, and this is very important, is that this particular unit will not cool an entire room. It is designed to be a personal cooler, making the immediate area around you more comfortable, nothing else… but it does that incredibly well. Also bear in mind that this is an evaporative air conditioner, so it’s not really much use in very humid areas.

The two vents can be moved to direct cool air in different directions and there’s hosing you can also add to give it more reach.

This unit holds nearly two litres of water, enough for a couple of hours and you can attach a larger water bag to it for longer periods between refills.

During my initial testing and measurements, it was reasonably cool inside – a mere 37C (98.6F) Here are the results; set at its least powerful setting:

Ambient temperature: 37C (98.6F)
Humidity: 11%
Temperature of air at vent: 20C (68F)
Temperature 3 feet away (air from single vent): 24C (75F)

That was pretty amazing – and when temps hit 45C, I was still comfortable enough to work and not even breaking a sweat.

Of course, the further away you’re sitting from the vents, the higher the temperature, but placed on a desk around 3 feet away from me, I’ve been able to continue working in all conditions – with just a single vent blowing cool air my way. The second vent I direct at Niki the Wonder Dog’s bed.

Swampy Cooling Systems have a variety of models. The one pictured above is the MW1, a 12 volt model (110 volt adaptor available). At its least powerful setting, it draws just .8 amps (11.3 watts), which by air conditioner standards is nothing. It’s about the same as a small 12 volt desk fan. As mentioned, it only uses just over a litre of water an hour; so it’s great in situations where water supply is limited.

The MightyKool MW1 is powered by twin brushless double ball bearing motors that should last at least 20,000 hours. I was very pleased to discover it’s even quieter than the desk fan I had previously.

The MW1 is very light, just over a kilo (under 3 pounds). It’s a simple unit, but well constructed and easy to pull down and clean. The special cooling pads last around two to four hundred hours – and they are cheap to replace.

The Mighty Kool isn’t cheap, but what it does, it does very, very, very well. At the time I bought it, there was nothing else on the market that came even close to what this little powerhouse could do.

The other thing that impressed me about Swampy Cooling Systems was their level of customer service. I communicated mainly with Jack, the owner of the company during my original purchase and he was very attentive. Shipping it over from the USA with a few accessories was a worry as I was concerned about damage, but I think the MightyKool folks must be expert Tetris players too – I had never seen a box so well packed.

Thanks to MightyKool, I no longer fear heatwaves. It’s nearly 4 years since I bought it and I’m still of the opinion this is one of the better purchases I’ve ever made.

The MightyKool isn’t just a creature comfort; it can be a life-saver.

Heating Pads – Save Money & Slash Carbon Emissions

April 22nd, 2013.

Suffer from cold feet? You might be able to avoid energy-sucking space heaters by using a heating pad.

With my butt firmly planted in an office chair for anything up to 14 hours a day, I find my feet get really cold during winter and even in the latter parts of autumn and early spring.

If my feet are cold, the rest of me is too. It doesn’t seem to matter if I double up on socks or even if I have insulated footwear on – they are still like ice-blocks.

Last year I tried a less power hungry fan heater – 750 watts. It was OK, but my feet were still a little icy and given I pay for 100% wind power for my office; it was getting rather expensive – costing me around 4 bucks a day to run.

I guess that is a small price to pay for a degree of comfort; but it just seemed a bit wasteful to me considering it wasn’t really doing the job. If I didn’t have the green power option and my electricity was coming from a brown coal fired power station, it would have also been responsible for adding around 8-9 pounds of carbon emissions to the atmosphere a day.

Additionally, fan heaters dry out the air, so I was finding my eyes were getting very sore by the end of a day.

I had also tried sticking a small column heater under my desk on a low heat setting, but that didn’t work either.

I bought a heating pad late in the season last year; but never got around to use it. Now the cooler weather is starting to make itself known in Australia, I’ve been able to give it a whirl.

.. and what a difference. Toasty warm feet = no other heater needed. When winter arrives, I reckon an extra layer of clothing is all I’ll need.

The heating pad is providing a better degree of comfort using just a fraction of the energy. It heats to around 40C (104F). According to the vendor, it’s rated at 75 watts; but my Watts Clever unit (measures electricity consumption) puts it at 90 watts.

90 watts is around 12% the electricity consumption of my energy efficient fan heater. The heating pad will pay for itself in around 12 days of use and I’ll save hundreds of dollars extra this season.

Just a word of caution – given the nature of this sort of appliance, choose carefully. I’ve read some disturbing stories about poor quality pads having hot spots and even catching fire.

Don’t spill liquids on a heating pad, fold them or leave them unattended. Read the instructions carefully and examine the pad regularly for wear.

While I have a safety switch on my home’s switchboard that reduces fire and shock risk; I really don’t want to test it out :).

Blackout curtains – save energy and carbon emissions

January 10th, 2013.

(First published September 2008, last updated January 2013)

A recent heatwave reminded me that I need to get some blackout curtains for a few windows of my new digs. During the hottest part of the day, even without the sun directly shining on the glass, the amount of heat being radiated from these windows was amazing.

Blackout curtains just aren’t for blocking light or for summer conditions; they can be useful during winter too.

Around a third of home heating and cooling related energy loss occurs via your windows. Blackout curtains can help insulate your home, saving you money in heating and cooling and the energy savings can also assist in reducing greenhouse gas emissions associated with energy production and consumption.

Additionally, as blackout curtains are much heavier than normal curtains and assuming decent quality materials are used; you can expect them to last a long time.

How do blackout curtains work?

Blackout curtains have a backing that is made from a very tightly woven fabric, usually multiple layered, which blocks most of the light; with some brands claiming up to 99.9%. reduction

How much energy can be saved?

According to some manufacturers, blackout curtains can reduce thermal loss by up to 25%. If you’re spending a few thousand dollars a year on heating and cooling, the savings add up quite quickly and can offset the cost of the curtains within a short space of time.

Other benefits of blackout curtains

I hate noise.. I mean really, really hate it. Noise pollution is a major problem for many people and is one of the most underrated environmental threats. Excess noise has negative physical and psychological effects on people and animals. It seems there’s no peace in the burbs any more, even when we need it most –  at night time when we’re trying to sleep. Blackout curtains won’t soundproof a room, but they can help significantly reduce the noise level.

How much do blackout curtains cost?

This varies greatly with size and quality of materials of course, but for a set of 2 curtains 180cm ( 6ft) x 230cm (7.5ft); expect to pay around $50 – $75.

If you’re handy with a sewing machine you can also save a bit of money by converting your current curtains – just add the blackout liners that you can buy from a haberdashery store. As there’s varying quality in blackout liners, be sure to hold samples up to a strong light before purchasing to ensure it works sufficiently.

Blackout curtain tips

A couple of simple tips for using blackout curtains that will maximize your energy and greenhouse gas emission savings:

To get the most from blackout curtains, you need to ensure the gather is sufficiently high above the rod to block light from appearing at the top and that the rod is situated so that it minimizes the amount of light “leaking” out the sides.

During the cooler months, only have the curtains open when the sun is shining into the room or outside temperatures are warmer than inside. During summer, curtains should be kept closed as much as possible; even if the sun isn’t shining directly upon the window.

How stuff is recycled

November 22nd, 2012.

First published February 2010, last updated November 2012

Our busy modern lives disconnect us from all sorts of things – how food is grown, how goods are produced, our waste dealt with, and the processes behind recycling. The following is a brief overview how some products are recycled past the point of extraction from the waste stream.

Aluminum can recycling process

After arriving at a smelter and inspected, the crushed aluminum cans are shredded. The pieces are then heated to remove the paint and any moisture, after which the material passes over fine screens to remove contaminants.

The material is heated again to melting point (around 600C) and chemicals added to separate more impurities that are then skimmed off. Aluminium and other metals may then be added to bring molten material to the required alloy specification.

The molten aluminum is poured into very large ingots and once cooled and cleaned, sent through rollers multiple times until a thin sheet is produced; which can then be remade into cans.

It’s an energy intensive process, but the recycling energy savings are around 95% compared to mining and smelting from new raw materials and aluminium can be recycled an unlimited number of times.

Steel can recycling process

After arriving at a steel smelter, bales of crushed cans are placed in a furnace with other recyclable steel. Molten iron is added and oxygen is pumped into the furnace, which heats up to around 1700 degrees Celsius, for 30 minutes. By the end of this time, impurities have been driven or skimmed off.

The molten steel is poured into large ingots, which go through multiple rollers while still very hot until the desired thickness is achieved for making products such as cans.

While the steel can recycling process doesn’t have as many stages as aluminium cans, much higher temperatures are used therefore requiring more energy. Regardless, the recycling energy savings are around 62 – 74%. Steel can be recycled over and over in this way.

Plastic soda bottles and bottled water containers

This deals specifically with PETE (or PET) plastics (plastic resin code 1).The bottles are first inspected for foreign materials then sorted into colors. The bottles are then sterilised, crushed and chopped into flakes.

The flakes undergo another separation and cleaning process to remove remaining foreign materials. The flakes are then chemically reverse engineered by either methanolysis or glycolosis, which can restore the material to the original raw materials and blended to create new PET.

The recycling energy savings of plastic soda and water bottles is around 90%.

Glass bottle and jar recycling process

Glass bottles are separated by color and broken into small pieces, usually at a recycling center, in order to cut down on volume for shipping. They are then transported to a bottle making plant where the material is crushed. Magnets, filters and vacuums remove foreign objects such as labels and metals. The cleaned powdered glass, known as cullet, is mixed with raw materials and placed in a furnace which melts it into molten glass; ready to be formed into new bottles and jars.

Glass recycling uses only two-thirds the energy needed to manufacture glass from raw materials.

Paper recycling process

The paper is sorted according to quality and shipped to a paper mill where water is added in order to turn it into a pulp. Foreign matter is then removed by various filters and screens. Chemicals are added to remove the ink from the pulp. Depending on the type of process, de-inking can be a simple detergent process or one that may involve chlorine or other more harmful chemicals depending on the ink being removed. The ink used in newspapers and packaging these days is usually soy-based; however, copy machine and laser printed document “ink” is a plastic polymer burned onto the page that requires harsher processes to remove.

Once de-inked, pulp is flushed with more water and air is injected to form an inky foam that is skimmed. The remaining water is drained and reused. The pulp is then bleached – more often with hydrogen peroxide these days as chlorine can combine with organic materials to form dioxins – one of the most deadly of man-made poisons.

More chemicals may be added at that point and the final pulp is either pressed into sheets and dried or mixed in with virgin pulp.

Recycling paper uses about 60% less energy than making paper from new materials; however, each time paper is recycled, it loses quality – so in effect it is really downcycled each time. Given the wide range of processes that may be used, not all recycled paper is created equal from an environmental aspect.

Another product often recycled is motor oil – most people don’t realize that motor oil can be fully recycled into new motor oil as it never wears out; it just gets dirty. I describe the motor oil recycling process here.

As you can see from above – recycling isn’t all that straightforward and there can be a lot of chemicals involved. We all need to continue recycling of course, but reducing consumption is equally as important. For example, perhaps next time you feel like a can of soda, consider heading to the tap for a glass of water instead. Instead of buying newspaper, duck online and read it there.

Organic Material And Oil

November 19th, 2012.

How much organic matter is needed to create a gallon of crude oil (petroleum)? Literally a truckload – actually, many truckloads.

I was refueling  my ATV the other day and marveling at how far a liter of petrol (gas) carried me, Niki the Wonder Dog and some gear across some reasonably rough terrain. The environmental issues aside, I still find the amount of work a small amount of this liquid can do to be mind-boggling.

I’m also fiddling with an electric ATV, using solar power to charge the batteries. It takes around 8 hours for 260 watts of solar panels to charge it enough to give me 18 kilometers range, at less speed and carrying less. However, it’s not a very efficient charging system I’m using and the ATV is just a petrol version that has been somewhat crudely converted.

There’s an awful lot of energy stored in crude oil – which is one of the reasons we’re having troubles getting away from the stuff. It’s certainly very compact compared to the batteries I’m using. Of course, the electric ATV is a lot quieter and cleaner though; but anyway, that’s another topic for another time.

As you probably know, crude oil comes from plants and marine organisms that existed many hundreds of thousands of years ago. Dead dinosaurs may also have contributed matter, but it’s believed that it would only equate to a small percentage.

The most popular theory is that as organisms died, they piled up at the bottom of bodies of water and mixed with sediment. As the sediment accumulated, the intense heat and pressure generated turned this organic material into a substance called kerogen. Over time, this kerogen breaks down and becomes natural gas or petroleum.

So, how much of the original organic material is needed to make a gallon of oil?

Around 98 tons of it! That’s according to some old figures I dug up on the California Energy Commission web site, attributed to ecologist Jeff Dukes.

Mr. Dukes said the amount of plant material that went into the fossil fuels we burned since the mid 1700’s was equal to all the plants grown on Earth over 13,300 years (and that figure is over a decade old).

Think about some of the long trips you’ve taken or even how much gas you pump into your vehicle each week. Bearing in mind a gallon of oil produces up to 0.67 gallons of gasoline; my weekly figure (including my main vehicle usage) is around 9 gallons of crude oil equivalent. That translates to around 880 tons of ancient organic material a week or 45,760 tons of the stuff a year.

But it’s more than that – most of the goods and services we purchase have been trucked in from somewhere, so that adds to our fuel consumption.

What about biofuels?

Generally, biofuels are very land intensive and still require a great deal of material. The following are figures I found on the University of Missouri’s web site.

1 acre of corn harvested in 2012:
158.6 bushels of corn per acre
2.77 gallons of ethanol per bushel (56lbs each) of corn
439 gallons of ethanol per acre

1 acre harvested of sugar beets harvested in 2012:
23 tons of beets per acre
24 gallons of ethanol per ton of beets
552 gallons of ethanol per acre

1 acre of harvested soybeans in 2012
42.8 bushels of soybeans per acre
11.28 pounds of soybean oil per bushel (60lbs each) of soybeans
7.7 pounds of unrefined soybean oil per gallon of biodiesel
63 gallons of biodiesel per acre

1 acre of harvested canola in 2012
1557 pounds of canola per acre
0.383 pounds of canola oil per pound of canola
7.7 pounds of unrefined canola oil per gallon of biodiesel
77 gallons of biodiesel per acre

The above figures are just for the feedstock used to make biofuel – not the whole plant; and then there’s the resources that go into turning the feedstock into fuel. Granted, the waste and by-products can often be used in other applications.

Keeping these sorts of stats in mind (aside from just being interesting trivia) can help remind us how hard the earth has to work to provide us with resources – and that some of those resources are being used up far faster than Mother Nature can provide them; not to mention the damage we wreak through heavy usage.

Also, when we start using food crops as fuel or diverting agricultural land to fuel production, it’s a little frightening – the practice has been labeled a crime against humanity. However, another ancient petroleum source mentioned, algae, is showing promise in terms of cultivation and biofuel production. Other promising feedstocks that can be grown on marginal land includes switchgrass and industrial hemp.

Personally, I’m still looking forward to an all electric 4×4 with a reasonable range (and at a reasonable price); but I think I’ll need a few more solar panels :).

Bonus trivia:

Fossil fuels are a form of converted solar power (albeit a dirty form) – as without the sun the many ancient forms of algae and plants couldn’t have grown.


Gas saving tips