- Galactic scale energy -- in which the annual growth in US energy consumption over the last 350 years is shown to be a fairly stable 2.9% and that, were global power demand to grow at an annual rate of 2.3% for the next 345 years we would reach the point where we were consuming all the suns energy hitting land (and, in about 2500 years would require all the energy in the galaxy!)
- Peak Oil Perspective -- not surprisingly, talks about peak oil
- The last few posts have begun to bring together and summarize a number of themes that run through many of the previous posts. Among them are The Alternative Energy Matrix which examines a variety of different alternative energy sources in terms of a diverse set of criteria (abundance, demonstrated feasibility, intermittancy, public acceptance, efficiency, viability for different purposes -- electricity, heat, transport; etc.) and finds that they generally score lower than fossil fuels. Fossil Fuels, I'm Not Dead Yet examines the peak oil problem as a liquid fuels issue -- that is in terms of energy for transportation fuel. This theme carries forward in The Way is Shut which notes:
The good news is that there do exist energy flows and sources that qualify as abundant or at least potent. However, many of the alternatives represent ways to produce electricity, which applies only to about one-third of our current energy demand. The immediate threat is therefore the short term liquid fuels crunch we will see when the global petroleum decline commences within the decade.
2) The concept of an Energy Return on Investment Threshold suggests that fuels with an EROEI of less than 8 become increasingly problematic as the proportion of energy used to procure energy relative to the proportion that provides net energy for society's use starts to increase dramatically.