a) Bio-fuels are not all bad. First, those produced from cooking oil and similar wastes have a net gain; that is, very little energy is required to convert them into bio-diesel and waste is consumed rather than disposed of. Second, each vegetable has a different input/output ratio. Much of the discussion on bio-fuel has revolved around corn, especially the high food prices (and resultant reduction in total aid). However, corn ethanol is not economically viable and never has been. (It takes 1 unit of fossil-fuel energy to produce a potential 1.3 units). To understand the reason corn why corn-ethanol is produced, one must examine the power of the corn lobby and Mexico's willful, but avoidable (under NAFTA), importation of America's subsidized corn. Sugar cane, on the other hand, has an energy ratio of 1 to 8 (1 in 8 out). The real potential (and future) of bio-fuels rests on cellulosic ethanols; with advancements in technology grasses, stalks from harvested plants, or algae could have ratios as high as 1 to 36. National Graphic has published an informative article on the topic of bio-fuels and has summarized the information here.
b) Advances in technology do offer hope, but there is no magic bullet. Solutions can be offered but they must be implemented and accepted. Here, regulation and mind-sets often stunts the profitable distribution of products, e.g., the ZENN cannot be driven in Canada and the Tata OneCat pneumatic car will probably never hit North America. In the Cold North I still hear people lament over the cost of heat-pumps, despite the break-even point of seven to ten years and low emissions.
c) Despite a growing selection of green products, which I support, it is not possible for us to buy our way out of the growing crisis. The reason is that most people in the West consume and pollute much more than the earth can support. You can test this assertion by calculating your global footprint (the number of earths that would be required if everyone on earth had the same standard of living). So far, our demand has been sustained by other countries with a lower standard of living (and demand on the earth). Now that many countries are becoming developed there's less to go around; as a result, reduction, not consumption, is the key. Nevertheless, when you do purchase items it is important to do so responsibly. To examine the possibilities of responsible living check out Dockside Green. Purchasing a hybrid, electric, and fuel-cell vehicle has an added benefit: they do not idle. In Victoria an idling ban is being proposed to reduce air pollution; however, these cars offer the better solution (the best though is walking, cycling, or taking the bus).