Dear Rusty,

I heard a scientist on a TV program recently -
suggesting an alternative to coal-fired
power generation, which produces substantial
pollution, to separate the coal into carbon and gas.
Use the carbon in industry and burn the gas
to produce power and drive cars with two-thirds
less pollution.

Can you/or anyone - contribute any more information?

Yup, Coal gasification/SynGas/Producer gas.

You take some coal (a good high energy fuel) or even wood, you heat it (which uses energy) or burn it (which uses energy) in an oxygen-starved environment and you release volatile highly reduced (hydrogenated) fractions: a lot of hydrogen and probably some lighter hydrocarbons like methane, methanol, ethane, ethanol etc.

The left over carbon is, yes, present in a lump, not in the atmosphere. I'm not sure how much "industry" wants it now that it is not a hydrocarbon.

Historically, to make the process energetically and economically efficient, to get the most fuel out for your heating energy budget, you also add steam to get more hydrogen, and to consume the carbon to carbon monoxide (also a fuel). You may recall "town gas" and similar potentially fatal mixtures. So now, post use, the carbon is in the air again. Not doing this is a considerably more wasteful enterprise. It *is* cleaner, but if the aim is to get the most out of any given power source, it does not achieve this. That reduced pollution cost up to half the energy. The inefficiencies further add up when you transport and retail the stuff, then attempt to efficiently run a high power fuel cell. Perhaps better to burn the coal in a very efficient coal power station with scrubbers.

I believe hydrogen will be a very expensive "premium" high performance fuel in vehicles that need to save weight in batteries. Joe sixpack attempting to convert his commodore will just about be willing to cram into a daihatsu instead.

The original post was about how to get a house and transport within an energy budget that can be achieved by home generation. I just don't think the typical house+car energy budget can, by a factor of five to ten (ish). A very frugal house+subcompact might (at considerable expense), but that isn't typical (though not unheard of) in our and particularly yank culture.

I like the wood option, its renewable. Anybody seen those pictures of wartime cars run on producer gas?

Cheers,

Rusty.

Whoops, been told by flatmate that I mixed a couple if steps there (been a long time since high school chem). Gasification produces hydrogen and carbon monoxide both, the steam addition allows more hydrogen and the removal of carbon monoxide as carbon dioxide. You still need a lot of energy to gasify. You still need a place to put the carbon dioxide.

How many hundreds or thousands of hectares of forest would be required to capture the carbon dioxide output of such a plant?

Reining in the Watts,

Rusty.

Foxy,

What you are suggesting has been built and running for decades in South Africa by Sasol producing fuel from gas. However, the gasification process is very energy wasteful, and the carbon emmissions are high.

The viability of the project is that it produces high value fuel from very poor quality coal, not that it is environmentally friendly.

Half the cars in Europe ran on brown gas during the second world war. I think there was a company in Finland commercially building units to fit to cars and trucks. It by no means is any cleaner than what we do now.

Heating and air conditioning is one area where technologies exist to save on huge amounts of power from the grid thereby allowing us to use that saving to run cars. But it would take a huge shift in government attitudes to implement it and they would actually have to grow a brain. Read up on Glauber's Salt(Sodium sulfate decahydrate) and heat energy stored in the phase change of certain salts. People could be keeping their homes warm in winter for nothing. The tech can also be used to keep homes cool reducing the need for aircon.

There's a lot more we can do with solar also, more than just PV cells and water warming.

The Mistubishi soon to be released can travel 160-180 kms. and takes 7 hours to recharge, making it a something of a toy. A high-powered sports car, very expensive, can travel up to 400kms, but there is still the problem recharging. Hydrogen-powered cars - too expensive and they don't know how to safetly store the fuel.

We are stuck with fossil fuels for the forseeable future, so there is not point in discussing the subject.