Force of nature

As Japan struggles with the aftermath of the Tōhoku earthquake - including a death-toll likely to top 25,000, more than 2,750 injured, 400,000 homeless and an estimated economic cost in excess of USD100 billion - confidence in civilian nuclear power across Asia has been badly shaken.

Driven by public concern, governments in Bangkok, Beijing, Delhi, Hong Kong and Seoul have all - to varying degrees - been backing off from their previously strongly pro-nuclear positions. Amazingly, given that it occupies a hot seat on the Pacific Ring of Fire, Indonesia is the only Asian country to say its nuclear plans are firm.

It remains to be seen to what extent short-term anxiety about the possibility of a melt-down at Fukushima Dai-ichi - and the vast amount of hot air generated through comments about other nuclear facilities around the region - will translate into project cancellations but stronger scrutiny is certainly welcome.

If you detect a certain jaundiced perspective on my part about the anti-nuclear lobby, that is because I used to be a paid-up subscriber. The threat of climate change and the dim prospect of renewable energy being able to scale up in time to replace the world's fossil fuel-fired generating capacity persuades me that that ramping nuclear energy for base load generation is the least bad option.

Nukes not the silver bullet

Those nervous about the impact of earthquakes on nuclear power plants should also have pause for thought about China's plans to double hydroelectric generation by 2020, primarily by building a string of new dams in geologically unstable Southwest of the country. That said, nuclear power is not a silver bullet for solving Asia's energy challenge and clearly other clean energy sources need to be part of the mix.

Among the lesson's to be drawn from Fukushima Dai-ichi - apart from not installing back-generators in the basement - surely one is that seismic activity is indicative of a significant and largely untapped clean energy source that can usefully be added to the mix: geothermal energy.

Consider some numbers for a moment. The Tōhoku earthquake had a magnitude of 9, releasing the equivalent of 2 exajoules or 555,555,555,556 kilowatt hours of energy in six minutes. That's about enough to meet the total energy needs of China or the US for a week. It would take all six reactors at the stricken Fukushima nuclear plant, running continuously at full capacity, 13.5 years to generate that much energy.

Please don't think for a moment I'm suggesting a far-fetched scheme to capture the energy of earthquakes. The numbers merely serve to illustrate the point that there's an awful lot of pent-up energy in the earth's crust which gets released in geysers, hot springs, volcanic eruptions and numerous earthquakes every year. All of these are manifestations of the continuous loss of heat from the earth's interior.

Of particular interest is the potential for geothermal energy generation. In 2008 the US Geological Survey (USGS) announced the first national geothermal resource estimate in more than 30 years. The results of this assessment indicate that full development of the conventional, identified systems alone could expand geothermal power production in the US by about 260 percent.

Geothermal under the radar

What really jumps out, however, is the USGS finding that: "The resource estimate for unconventional enhanced geothermal systems is more than an order of magnitude larger than the combined estimates for both identified and undiscovered conventional geothermal resources and, if successfully developed, could provide an installed geothermal electric power generation capacity equivalent to about half of the currently installed electric power generating capacity in the United States."