Wednesday, 18 March 2009

Peak Oil: Will We Freeze or Roast?

When I was in graduate school in the early 1990s, M. King Hubbert was a name known only to fellow energy nerds. Now, he's so popular you can get regular news alerts.

Hubbert developed a mathematical model describing how production from an oil well or entire oil producing region tends to increase at a predictable rate, until it hits a - predictable - peak and then declines. Hubbert used his model to predict the year of peak oil output for the United States, and it has been used more or less successfully for other oil producing regions since then.

In addition to forecasting output growth for particular regions, the Hubbert Curve and peak oil theory can be applied to oil production for the world as a whole. But as recently as 2005, the International Energy Agency (IEA) dismissed the concept. Mainstream energy agencies tended to assume that oil production could increase indefinitely as new investment and technology are brought to bear. If a peak exists, they argued, we are nowhere near it.

This matters because when the world's leading climate scientists prepared their 2007 report on global warming trends and impacts, they turned to the IEA for their best estimates of fossil fuel consumption. The IPCC works by consensus, and its reports tend to refer only to the most authoritative sources. The IEA estimates showed that conventional fossil fuel use would continue to grow without end, and this prediction is reflected in all the pessimistic warnings about global temperature increases and climate change.

Times have changed. The IEA is now predicting that we will reach global peak oil between 2020 and 2030 (more pessimistic scenarios argue that we reached the global peak last year). So oil production will top out much earlier than anticipated.

Less petroleum production means fewer petroleum-related greenhouse gas emissions. In fact, manyindependent models suggest that, once peak oil (and coal) is factored in, we simply can't burn enough traditional fossil fuels to reach the worst-case global warming levels.

Let me repeat that: Most climate models that incorporate peak oil theory predict a temperature rise of less than 2 degrees Centigrade. A major change to be sure, but far less than the IPCC's "business as usual" scenario for global warming.

So, this is good news, isn't it? Climate change is solved because fossil fuel production will decline sooner than predicted, right?

Not so fast. What are we going to use for our vehicles when the oil starts to run out? Shall we simply switch off the lights and freeze?

In 2006, Alex Farrell and Adam Brandt, researchers at the University of California at Berkeley's Energy and Resources Group, published a paper that examined the cost, availability and climate change implications of substitutes for conventional petroleum. These are liquid fuels derived from heavy, difficult to process resources like tar sands, oil shale, and coal.

The Berkeley team found that it would be commercially viable to produce synthetic petroleum from these heavy fuels at oil prices of less than US $50 per barrel. What's more these resources are so abundant that they would keep pump prices relatively low.

In other words, peak oil means less petroleum, but not an end to fossil fuels. For those who worry that peak oil means society will collapse into "Mad Max" - style anarchy, that's good news.

The bad news is that these fuels have a much greater climate change impact than conventional oil. Using tar sands and heavy oil results in about 50% more CO2 per unit of energy than regular petroleum. Synthetic fuels made from coal nearly doubles the greenhouse gas emssions, and using oil shale could result in up to 3X the emissions per unit of energy. To quote the authors:

"Overall...the oil transition is not a shift from abundance to scarcity: fossil fuel resources abound. Rather, the oil transition is a shift from high quality resources to lower quality resources that have increased risks of environmental damage, as well as other risks."

Sadly, peak oil is not the solution to climate change. If anything, a poorly planned response to peak oil could accelerate global greenhouse gas emissions growth.

There is an alternative. We have the technical know-how to produce energy from low- or zero-emission sources. Solar, hydropower, wave and tidal, wind, and geothermal energy are clean sources of hydrogen and electricity, and carefully chosen biofuels can provide high energy-density liquid fuels.

Scaling up these clean energy technologies at the rate required to compensate for peak oil and limite climate change is a challenge. But as discussed in an earlier article, the required investments by governments, corporations and communities are no larger than other causes on which we have spent billions. The need is arguably as great, if not greater, because poorly planned energy investments made today will have a huge impact for decades to come.