Toward a more sustainable world

1. Drive a smaller car or drive a little more slowly, minimise your driving, walk or ride a bike some of the time,
2. At home, switch off lights when you don't need them, use long-life light bulbs, switch off your water heater if you are going away for a few days, perhaps empty your freezer and switch that off if you are going on holiday;
3. Insulate your house;
4. Use heating sensibly: do you really need to heat your whole house? Perhaps you could just heat the kitchen in the day time and the lounge room in the evening? Sometimes it might be more efficient to use a little bar heater to warm yourself rather than trying to warm the whole of the room that you are in. Also see my page on greenhouse responsible heating
5. Try to minimise the amount of rubbish you produce. Take cloth bags to the super markets rather than using plastic bags once and throwing them away. Re-use bottles and jars; perhaps brew your own beer rather than buying it in use-once-and-throw-away bottles.

Green electricity

It doesn't cost much more than ordinary power, because a large part of our power bills is the supply charge anyway, but it must make a difference in reducing greenhouse gas production.

Solar water heating

I've written a little more on solar water heating.

Wood fired heating

In Australia most electricity is produced by burning fossil fuels. So electrically powered heating, whether by reverse cycle air conditioners or by simple radiators, is largely heating by burning fossil fuels. However, reverse cycle air conditioners should give you more heat per kilogram of carbon dioxide produced.

In the cooler part of the year, water too can usefully be heated by burning firewood. See wood-fired water heaters.

Chopping firewood for the stove will also give you some exercise, which most of us need. There is also an interrelationship between firewood, overpopulation, greenhouse and air pollution that you might consider.

Keep your car longer

People are sometimes told that if they want to be greenhouse friendly they should get rid of their old, inefficient, polluting, car and buy a new one. There is much validity in this, so long as the car you replace the old one with is significantly more fuel-efficient than the old one.

But what also must be considered is the balance between the amount of additional pollution that might be produced by running an old car compared to the huge waste of material involved in scrapping the old car and replacing it with a new one. There is not a lot of recycling of material from old cars. They might sit around in a wrecker's yard for a few years, then after a few parts have been taken to keep other peoples' old cars going, they will be crushed and melted down for the steel that's in them.

If the engine in an old car runs well it should produce little more pollution than a new car. (It does depend a bit on what sort of pollution we are talking about.)

I have a car that has done 330 000 km and was still going strong when I retired it a couple of years ago; although it was getting draughty and the heater no longer worked. A friend has a car that has done very nearly 400 000 km, and still going strong. If some cars can do it, why shouldn't all be able to? Consider how much less waste there would be, consider how much further your income would go if you only had to buy a new car every twenty or thirty years rather than every four or five years.

Car manufacturers would have to build more quality into cars if they were all to last 300 000 km+, but I suspect that the cost of doubling the potential life of a car might be an additional 10%. See 'Building for a longer life' below.

Drive a smaller car

1. They consume about twice as much irreplaceable fossil fuel per kilometre compared to a compact car;
2. Similarly, they produce about twice as much greenhouse carbon dioxide and other atmospheric pollutants;
3. They take much more resources to construct;
4. When eventually scrapped (and you should always think about eventual disposal when you buy something) there is more to dispose of;
5. If you collide with someone in a smaller car, you are much more likely to kill that person;
6. They drive like trucks!

Drive more slowly

For years I have driven at 90km/hr, as much as possible, rather than the Australian open-road speed limit which is usually 110km/hr, because I was aware that the higher speeds waste energy, fuel, and produces unnecesarily large amounts of greenhouse gasses. I have also experimented with driving at 70km/hr on open roads with very little traffic, and found that fuel consumption per kilometre travelled is perhaps 20% less than when travelling at 90km/hr.

I was recently surprised to find that my car (a Honda Jazz) – driven at relatively low speeds because of mountain roads – would go up and down a 1000m mountain and average about the same fuel consumption as when travelling a similar distance on level roads at higher speeds! (The Honda Jazz can display fuel economy in litres per hundred kilometres as you drive.) Think how much energy is needed to lift a one-tonne car 1000m, and then consider that a similar amount of energy is used in pushing a car along a level road at 90km/hr. (In both situations the Jazz used about 5.8 litres per hundred kilometres.)

In a sane world which was running out of petroleum and had dire climate change problems due to excessive burning of fossil fuels highway speed limits would be greatly reduced. What has that to do with this world you might ask!

1. Fossil fuel reserves are finite. We are burning them at a far greater rate than they are being replenished.
2. Burning fossil fuels changes the carbon within them from a solid form beneath the ground, where it does no harm, to a gaseous form in the atmosphere where it does harm.

"The world's problem is as follows. We now consume six barrels of oil for every new barrel we discover. Major oil finds (of over 500 million barrels) peaked in 1964. In 2000, there were 13 such discoveries, in 2001 six, in 2002 two and in 2003 none. Three major new projects will come on-stream in 2007 and three in 2008. For the following years, none have yet been scheduled."

The big question is, what can we use to replace fossil fuels as an energy source? Some answers are given on these pages.

When fossil fuels are burned they produce gasses (most significantly carbon dioxide, but others as well, including sulfur dioxide) which are released into, and pollute, the atmosphere. This is a cost which should be taken into account when defining what the 'level playing field' is, but it usually is not taken into account.

To fairly compare the cost of sustainable or alternative energy with fossil fuels one should add in the costs of capturing and disposing of the CO₂, SO₂, and other pollutants. As of November 2008 no-one has built a full-scale operational fossil-fuel-burning power station that captures and disposes of its waste gasses, so there is no level playing field.

In any case, the fossil fuel industries are powerful and entrenched; they have a huge political clout. Governments in countries such as Australia and the USA have allowed themselves to be influenced by the strong fossil fuel lobbies.

At present the fuel cell engine (FCE) is very expensive compared to the internal combustion engine (ICE), but good progress on this is being made as there has been a ten-fold fall in cost from earlier versions. The ICE has the advantage of very large scale mass production, and there is no doubt that the cost of the FCE will drop as its production numbers increase.

Western nations are currently highly dependent on petroleum supplies. As much petroleum is imported from the politically unstable Middle East, the attempts of nations to secure their fuel supplies has lead to some dirty politics. (See The Real USA.)

The hydrogen for the FCEs can be produced electrolitically from water. Some form of sustainable energy could be used to power this process. There could be a closed cycle with some form of solar energy used to break water up into hydrogen and oxygen and then the hydrogen and oxygen being recombined into water in the FCE. No emissions, no pollution.

There is a long way yet to go before hydrogen powered vehicles take over from ICE powered vehicles, but the change, if it comes, will be a big step toward sustainability.

While it is true that it is quite impossible to grow sufficient wood to replace our present rate of fossil fuel consumption (there just is not enough land available), wood could be at least a part of the solution. My impression is that there is a lot of money going into hydrogen fuel cell powered vehicle research, but very little into research on sustainable production of liquid or gas fuel from wood.

Wood is still a major source of energy in the Third World. A useful site is Regional Wood Energy Development Programme in Asia. The Food and Agriculture Organisation of the UN has a site on Promoting sustainable wood energy systems.

It hardly needs be said that use of wood as a fuel must be done sustainably. Plainly logging or wood-chipping of old growth forests must not happen; it is environmentally destructive.

Comparative cost of energy

The typical retail cost of one kWh of electricity in SA is $0.17, or $170/MWh. As 1MWh is equal to 3.6GJ this converts to $47/GJ for electrical power. So firewood energy is about 21% the price of electrical energy.

Energy Calculator discusses these matters in more detail and allows you to calculate your per GJ energy costs from a variety of fuels.

Obviously, heating oil and electricity are much more convenient energy sources than is wood in most cases.

See also Energy conversions and definitions.

"The (Australian) Federal Government has made a policy decision that 2 per cent of Australia's electricity will be generated from renewable resources by the year 2010 and is actively encouraging the development of alternative energy technologies. Hot Dry Rock (HDR) geothermal energy is a vast, environmentally benign, economically appealing energy source. HDR is a conceptually simple technology.

Water is injected into a borehole and circulated through a "reservoir" of hot cracked rock several kilometres below the surface. The water is heated through contact with the rock and is then returned to the surface through a second borehole where it is used to generate electricity. The water is then re-injected into the first borehole to be reheated and used again."

A company has been floated to set up a pilot plant to demonstrate the feasibility of this technology. Here is a link to their Web site; Geodynamics.

Geodynamics has prospects in the Cooper Basin (SA), Muswellbrook (NSW), Eromanga Basin (QLD), and the Hunter Valley (NSW). Their Web site provides useful information on the hot rock electricity generation principle.

Apparently the original source of the heat is the radioactive decay of some elements within the hot dry (granite) rock. All granite is slightly radioactive. Thus, unlike most energy used by mankind, the primary source of hot rock energy is not the Sun.

Scientists are developing ways around this problem. One solution being researched at the Australian National University is to use large dish solar collectors to heat ammonia gas (NH₃) to a sufficient temperature for it to 'break up' into its constituent nitrogen (N₂) and hydrogen (H₂) gasses. These gasses can then be piped to wherever energy is required and, as needed, the nitrogen and hydrogen are recombined to form the original ammonia, with the release of the original solar energy in the form of heat. This process is shown symbolically in the graphic below.

Some ways we might use are:

• Much smaller and lighter vehicles;
• People moved by bus, tram and train rather than in cars;
• If private cars are used at all, they will carry a higher 'payload ratio';
• Freight by train rather than truck;

What will be the fuel of the future?

1. Various forms of natural gas;
2. Biofuels;
3. Electricity stored in batteries;
4. Hydrogen;
5. Ships could go 'back' to sail;
6. Solar hybrids: wind generated electricity converted to liquid fuels, solar thermal energy used to produce liquid or gaseous fuels, etc.;

1. Natural gas will not last much longer than liquid petroleum;
2. Biofuel production requires a large area of productive land. This land will be needed to feed people, and in any case there is simply not enough land to produce enough biofuel to replace our present rate of consumption of liquid fuels. All biofuels are ultimately powered by the sun; the conversion efficiency from solar to biofuel is very low, around 0.2%.
3. Even the best of modern batteries store far less energy per kilogram than is in liquid petroleum.
4. Hydrogen it a very light gas that cannot be liquefied except if kept very cold. Even then it is light and a very large tank would be needed to hold an amount of fuel comparable to a tank of petrol or diesel. If contained as a gas then it must be kept under very high pressure and still little energy can be contained in a given volume compared to petrol. How hydrogen can be manufactured sustainably in large volumes remains to be proven. Even moving hydrogen by pipeline has its problems, much larger diameter pipes would be needed than to transport a comparable amount (in terms of energy value) of natural gas.
5. Sail as a means of moving ships was almost universal up until the rise of steam. Sail went into decline in the nineteenth century and had almost disappeared as a commercial means of moving ships by the middle of the twentieth century. There have been attempts to resurrect sail, in a new, mechanised and aerodynamic form, in the last few decades. With rising petroleum prices, and the need to reduce greenhouse gas production, sail could make a come-back.

A person can travel on an electrically powered bicycle weighing around 30kg at a speed of about 20km per hour; although at present these only have a range of around 30km.

The vehicle of the future may well come somewhere between these two extremes in weight, speed, and fuel consumption. It may be similar to a very light-weight, aerodynamic, and low powered version of the current very small car.

The car of the future may not be very far off; it is quite possible that the heavy 4WDs and big V8s that people are buying in 2005 may become unusable in a few years time because of steeply rising fuel prices.

"Prof Lovegrove's idea for a 'fully sustainable future' would have farmers growing salt water algae - which he says produces about 40 times more biomass than food crops per hectare. Once harvested the algae would be 'gasified' at 700 degrees Celsius in massive pressure cookers powered by energy from solar dishes. The resulting methane gas would be put under another high-pressure industrial process and emerge as methanol."

"A 500-square-metre parabolic dish [to be built in Whyalla, South Australia] - that's bigger than an average house block - consisting of 424 mirrored panels will be erected over coming months as a prototype for a solar farm planned for Whyalla, South Australia. Private company Wizard Power has partnered with the solar thermal boffins at the ANU, led by Keith Lovegrove, to build what they say will be the first renewable energy power station capable of producing electricity around the clock by the end of next year. Combined with an ammonia-based storage system, the solar thermal concentrator will not only create carbon emission-free base load power, its technology could also be used to one day solve the widening oil crisis and supplant high-earning coal exports, Prof Lovegrove said in Melbourne this week."

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