I think there is a lot of point in a carbon tax. In any market, if prices don't reflect the true costs of goods or services, people use too much or too little of them. In the case of fossil fuels, we are not pricing in the cost of mitigating the effects of global warming. If we were, consumption of fossil fuels would would be much lower than it is currently because the price would be higher. The higher price would force people to reduce consumption and invest in alternatives as these would be more economic.

I would prefer to see the tax on the CO2 rather than energy as it will help to make the lower carbon technologies relatively more economic compared to fossil fuel burning and encourage investment in these technologies which we need as a response to Peak Oil.

As for protecting the poor, a system of rationing like Tradeable (carbon) Energy Quotas would be much fairer in the medium term but I think we need a carbon tax now while such a system is designed and put in place. That would allow the poor to sell their ration for cash if they didn't need it.

I think there are many opportunities for increasing renewables. We haven't begun to exploit wave and tidal power in this country. Off shore wind has potential as does solar. I'm more skeptical about the role of biofuels except coppiced timber for heating in rural areas which could be expanded over time (and provide much needed timber as well) simply due to insuffcient farmland which we need for growing food. Also, I doubt there is much potential for a lot of on shore wind because it will be opposed by locals and will adversely impact the landscape if done on a massive scale and the micro-wind turbines don't seem to work that well in urban areas dues to eddies etc. Surely there is further small scale hydro potential on our river systems at reasonable cost?

I see the main problem with renewables as the eratic output which means we need the ability to store energy or provide back-up generation. Output can be unpredictable, like wind and solar, or at certain times, like solar and tidal. Really, the cost of back-up generation like pumped storage, battery storage, or gas turbines should be factored into the cost of renewables when making a fair comparision with nuclear and carbon capture technologies which are by nature reliable in output. This doen't mean renewables would necessarily be uneconomic if a proper system for carbon taxation was introduced. We could then get rid of the inefficent and ineffective grant programmes and the ROCs etc and let the market do its work.

Required reading for Tradeable Energy Quotas (TEQs)

http://www.teqs.net/

to answer One of your points Biofuels is only good if one does not cut down rain forest as is happening in Brazil! They are planting Palms to get palm oil because of the desire for the west to be green.

Biofuels is good where for example the sugar companies make fuel (ethanol) out of the left overs from making sugar.

Personnel - y I think a Carbon Quota would be good it would encourage people to buy or lease solar thermal /PV equipment for there homes, although I do not think wind turbines on houses are practical for most of us.

I saw just that put up by windsave it is in what I believe is a very windy spot and its only produced 180 k watt in 5 months