Too often, debate about alternative sources of energy is exhausted on comparisons of monetary cost with fossil fuels – as if today’s prices for fossil fuels are guaranteed to stay the same or lower for the thirty to forty year time horizon over which any new energy-related project would have to be evaluated. This slightly long post at The Oil Drum provides a useful overview of the nine challenges of alternative energy:

The nine challenges posited by the author of the post are:

1. Scalability and timing
2. Commercialization
3. Substitutability
4. Material input requirements
5. Intermittency
6. Energy density
7. Water
8. The law of receding horizons
9. Energy returned on energy invested (EROI)

You can read more about each challenge in the original post, linked above.

I would add in conclusion that all these challenges have in common the themes of (a) complexity and (b) long time lags from planning to actual results. Thus, the author is absolutely right in pointing out the need for earnest debate on the nine challenges he sees. We must move past the simplistic debate that exhausts itself in comparisons of monetary costs. Most of these monetary comparisons are inherently flawed anyway, because they implicitly assume optimistic fossil fuel prices.

Whenever you nod in approval at statements such as “solar PV electricity costs 30 cents per kWh compared to 15 cents per kWh from conventional fossil fuel based electricity”, you should realize that you just bought into the implicit assumption that fossil fuel sources will be available at the current price of fossil fuels over the next 30 years that the solar PV plant will operate. If you don’t buy the implicit assumption, should you continue to believe the careless statement that renewables are more expensive?

Evolution by natural selection led to humans who worry much more about tomorrow than for next year. All the more reason to set aside simplistic monetary evaluations and force ourselves to think about next year too, just as the author of this post urges us to.