efficiencies -- which means that fuel cells and micro turbines have higher emissions than large power plant as well as higher costs
Once upon a time, not so very many decades ago, experts were held in awe. Surrounded in mystique, these high and mighty beings descended from their ivory towers to direct governments in leading the people in lives of well-being, prosperity and peace. But as the world got more complex, the experts gradually lost touch with real world matters, such as who is going to pay the cost of all their good advice. The result was spiralling public debt and the unravelling of state institutions. The age of the expert came to an end.
It was superseded by the era of the economist, creatures who look upon experts as dangerous spendthrift elements that governments need to keep under control. A natural counterweight emerged to these bean-counters in the form of think tanks and learned societies. They, quite rightly, do not believe the world should be run on monetary principles alone.
All very well and good, or is it? Governments, alas, are now bombarded on all sides by advice which is often anything but expert. Meantime the real experts don't get a look in. There are signs in the world of electricity generation that prophets make lousy replacements for experts -- and economists do not hold all the answers. The danger is that governments will forge policies based on false pictures of what technology can achieve. Micropower and fuel cells fall into this category. If our politicians become convinced that the future lies with every consumer having a fuel cell in the outhouse, they will, quite logically, plan accordingly. This could have dire and negative implications for the energy infrastructure, for carbon dioxide emissions and for energy costs.
A series of myths abound about micro scale power, such as the one in a government report which would have us believe that fuel cells "offer only limited efficiency advantages over CCGT for large scale power generation." Well they don't. The best examples are about 20 percentage points below combined cycle gas turbine (CCGT) levels, and even if their efficiency improves in the future, the hydrogen which drives them needs to be produced by a process which is, at best, about 75% efficient. That means that CCGT, or renewables, are still a better economic and environmental bet for electricity generation. Even when fuel cells operate in combined heat and power (CHP) mode, they are not going to be as efficient (and probably not as cheap) as CCGT plus CHP. This is because the difficulties of matching heat and electricity demands are rarely acknowledged, let alone assessed, by any of the think tanks. At the domestic level, where fuel cells are supposed to come into their own, matching heat and electricity demands is particularly difficult: very little heat is needed during the summer and the ratio of peak demand to average demand -- for both heat and electricity -- is around ten to one, which makes sizing the plant very difficult. This point is rarely discussed, nor is the highly relevant fact that small scale systems have much lower efficiencies -- which means higher emissions and higher costs. Costs may fall, but the efficiency gap is more intractable.
Small power systems and fuel cells do have a role, but one where they supplement large scale power generation, not replace it all. Their huge potential, however, is likely to be damaged by some of the wild claims currently circulating. Indeed, all the technologies -- renewables, micropower and fuel cells -- have bright prospects, alone or in partnership. But expert attention needs to be paid to structuring both an electricity system and an energy system which provide the best combination of efficiency, environment, and cost.
It could be that the century of the prophet, the expert and the economist, working in perfect harmony, is upon us. Nothing but an optimist is Helmsman.