interesting post in his blog Cassandra's legacy.I guess my own take is rather similar to Bardi's, perhaps slighty more pessimistic. I write in Ugo Bardi in an Garden Earth:
Of principal, environmental and even economic reasons, our future energy supply should be based on renewable energy. A panicky dismantling of our fossil fuel dependency may cause serious problems to society. It is nevertheless important, exactly because of that, that the transformation starts as soon as possible. Fortunately, some impulses for transformation came in the 1970s with the first oil crisis and more came with the oil prices hikes in the 2000s as well as with increasing awareness of the impact of climate change. There is no point in, not needed and also not possible to determine how much of our future energy mix that has to come from the sun, from wind, from hydroelectricity or from one or the other forms for biomass. We know quite well the draw-backs of large dams for hydro-power, and the use of water might also compete with the use for irrigation, which sets quite some limitations. We have not really figured out too many drawbacks from wind turbines, even if there are objections re impact on bird life, aesthetics etc. The main issue around biomass is the competition for land with farming and wild “nature”. For sure we need to expand the use of solar energy in all its three forms, and possibly some other hitherto unknown forms. In the longer term, it is likely that solar energy can provide us with most of the energy we need. Perhaps future photovoltaic cells can reach an efficiency of around 25 percent, which is double the current rate, and the cost of self-production could come down to between one or two cents per kWh (IIIEE 2007), ten percent of current price. Nuclear power is not an interesting technology from an energy-efficiency perspective or from a safety perspective. It is a prime example of how something can be "profitable" because so many costs are externalised. It builds of exploitation of nature, other people and future generation and massive subsidies from society (in the form of infrastructure, research, insurance etc.). In addition, the complexity in technology and society that has to be there for operation of nuclear power is hardly desirable and not possible to guarantee over time.
It was just natural for humans to have a predisposition for sweet food; energy was always short in supply and our predecessors were rarely in the risk zone for diabetes. In modern society, where sugar is cheap and abundant, however, the craving for sweets needs to be kept in check. The consequences of not doing it are fatal. It is the same for our society at large when it comes to energy. Fossil fuel is like we found an enormous bag of candy that someone left, and we just eat and eat. Too much cheap energy screws up the metabolism and we have to voluntarily restrict our use. Energy scarcity is the only “natural” limitation to a total human expansion and conquest of everything and we should be happy that energy is not in unlimited supply. With our tendency for exaggeration we most certainly will destroy the basis for our own survival with an unlimited supply says Janken Myrdal (2008) and I agree with him. If we first adapt ourselves to a non-expansionist way of living, then cheap and easily available energy can be a boon. But we certainly need to ensure that the energy poor of today can get more access to energy.