Buried Sunshine and the Energy Supply Chain

In my last blog I pondered three questions:
1) “Instead of burying CO2 at various locations around the world, could we not convert CO2 into a fuel ?”
2) “Is all the public focus on CO2 emissions justified, given the threat of a warming Arctic?”

3) “Why is it that wind, solar, and biofuels are more expensive than coal, oil, and natural gas when the supply chain efficiency for the first three is much greater than the last three?”
The simple answer to (1) is, “Yes”. The carbon cycle operating within our biosphere is fundamental to life. Referred to as the ‘biogeochemical cycle of carbon’, CO2 does provide the fuel that powers our atmosphere. Currently the research effort expended in emulating and harnessing nature’s energy factory – i.e. photsynthesis – has been limited. However, during a very informative session today hosted by the International Energy Agency (IEA), it was clear that in order to meet the ‘450 Scenario’ described in the recent “World Energy Outlook 2009” report, the amount of energy generated via photosynthesis (biomass) is second only to onshore wind turbines up to the year 2030. As I listened to the statistics and watched the graphs scroll by, I wondered if we could use the concepts of biomimicry to re-connect with our world and establish a sustainable society.
So, is all the media focus on CO2 justified? What does get ‘lost in translation’ within the mainstream media is the seemingly transparent interchange of the terms “Greenhouse Gas (GHG)” and “Carbon” and “CO2” emissions. The terms refer to completely different aspects of the climate story. As described in the article on Arctic warming, one volume of methane released to the atmosphere has the same effect as 25 volumes of CO2! What does get lost within all the opinions is that the carbon emissions reduction targets are based on the concept of ‘carbon equivalence’. This term implies that all GHG-type components within a waste stream – e.g. flue gas – are translated into a ‘CO2 equivalent’ value for atmospheric effects. Thus, when we hear of CO2 emissions reduction targets, we need to ask, “Do you mean CO2 or CO2e (equivalent)?”
The concept of ‘CO2e’ goes back to my belief in fundamentals. By distilling a complex issue down to fundamental components, I find that the process of understanding the key issues much easier to absorb. Such is the case for my third question: why is it that wind, solar, and biomass energy sources are more expensive than coal, oil, and natural gas? I am guessing that your initial response has its roots in conventional supply/demand economics: if a resource is plentiful and easy to tap, then the price of that resource will be relatively cheap. Well, that is true only if the externalities of the economic equation are ignored. At a recent session of the World Wide Fund for Nature’s One Planet Leaders Executive Programme in Sustainability, the WWF asked that I deliver a teaching session on Energy Fundamentals and Sustainability. As a graduate of the OPL programme, I saw the invitation as an opportunity to explain to the diverse audience that, without proper accounting for Earth processes, conventional ‘fossil fuel’ energy sources will always have an advantage over wind, solar, and biomass energy sources. This is due primarily to our economic pricing models ignoring the significant work that the Earth’s geological system does in order to create the coal, oil, and natural gas we use today.
Then let’s go back to fundamentals: as I described above, photosynthesis is a significant energy source (driven by sun energy, which is free). However, the efficiency of the photosynthesis process is quite low – approximately 2.5% maximum. So, when a plant or marine phytoplankton dies, the energy created by photosynthesis is absorbed into the ground, where the Earth geological processes very slowly convert the energy/mass mixture into coal, oil, and natural gas. This process takes approximately 5,000 to 10,000,000 years and has an efficiency of 0.0009%. Now, the ‘Buried Sunshine’ can be extracted from the Earth’s crust and burned in a thermal power plant to give us electricity. This process has a typical efficiency of approximately 35%. Overall, then, the efficiency of the process that produces coal, oil and natural gas is approximately 0.00001%. Compared to a Concentrated Solar Power (CSP) plant efficiency (up to 40% overall – sunlight to electricity delivery), an investment in such a low efficiency process as coal, oil and natural gas production is not very attractive. To illustrate even more clearly, let’s conduct a thought experiment: if every kWh of energy from the sun costs us £1, then what would be the electricity price from our CSP and natural gas-fired power plants in order to breakeven? £7/kWh and £10,000,000/kWh, respectively. Based on this relatively simple analysis, the Earth gives us £9,999,993 worth of ‘free’ services for every kWh of natural gas energy we extract from the Earth’s crust. I guess $150/barrel oil doesn’t seem so expensive…
It is clear to me, then, that the concept of Contingent Valuation must be better understood and included in our evaluations of energy supply chains before we can honestly talk about ‘Energy Sustainability’.