I tried that EIA site and was able to make some interesting graphs with the Excel data they provide. I think they answer many of the trend questions I had asked.

Thanks for pointing me to that site.

I don’t buy either point. First off, there are major questions about the numbers for natural gas and oil. For example, disputes over how much natural gas Russia ships to Ukraine and how much Ukraine extracts before shipping it south to Europe is at the heart of the recurring natural gas supply disruptions afflicting Europe.

As for excluding wind, geothermal and solar power generation: Why does BP include hydropower in its data if it is then going to exclude other sources of renewable electricity?

An alternative source if you really want to dig into data is the U.S. Department of Energy’s Energy Information Agency website, which is a data goldmine. See the World Energy Overview for one starting point. Note that the EIA overview’s Table 2.9 on world primary energy production presents renewables other than hydro as a separate category.

Bin Frequency
0 0
1000 0
2000 0
3000 0
4000 1
5000 5
6000 5
7000 9
8000 4
9000 10
10000 5
more 4

This has an interesting behavior when we consider that energy usage has an approximately linear (found by graphing the dataset)increase over time. But apparently the usage lately has bucked that trend and energy usage is now increasing more than average.

Gerard

Regarding your questions about the development path of tidal power, its similarities to wind power certainly help. In a 2007 story for Technology Review I reported found that:

Thanks to lessons learned by wind turbine designers, tidal power is already economically competitive, producing electricity at prices similar to wind power, according to feasibility studies by the Electric Power Research Institute, an industry R&D consortium. And it offers a big advantage over wind and other renewables: a precisely predictable source of energy.

As for the potential impact of tidal energy, here are some useful comments from British authorities aggregated by the British Wind Energy Association:

The World Offshore Renewable Energy Report 2002-2007…suggests that while a staggering 3000GW of tidal energy is estimated to be available, less than 3% is located in areas suitable for power generation. Tidal current energy is therefore very site specific, optimized only where tidal range is amplified by factors such as shelving of the sea bottom, funnelling in estuaries and reflections by large peninsulas…However, Scottish Enterprise comment that it is estimated that at least 34% of the UK’s electricity demand could be generated from tidal currents, which on a European level would be a contribution of nearly 5%.

Gerard