Our Fuel Cell Infancy
By M. L. Simon
I'd like to take a step back from the road to renewables and see what the road ahead looks like given where we are today.
So far we are doing best in the electrical generation area. Wind is poised to take up an ever larger fraction of America's electrical generation portfolio. Wind electrical generation is closest to being cost effective without subsidies, probably in the range of three to seven years. With subsidies it is already cost competitive.
Solar cells are probably fifteen to thirty years from being cost competitive. Solar will not be important until 2030 or so for the simple reason that they are coming down in price at the same rate as wind - about 50% a decade - but wind has a many decade head start. Still at that rate by 2025 renewables will make up a substantial part of the American power supply and by 2065 we will no longer be using fossil fuels.
That is truly amazing. We will be off fossil fuels in about 65 years. Incredible.
Coal is already in decline world wide at the rate of 1% a year. With no treaty agreements what so ever. We are on the right road. Coal is mainly used for electrical generation, currently one of the least efficient sectors of the economy. About two-thirds of the power put in to electrical generation comes out as waste heat.
There is an answer to this waste currently going into production. One of the latest commercial power supplies is designed to decrease the losses by a factor of three. It is a combined cycle gas turbine and fuel cell combination that gets an amazing 80% efficiency from natural gas. Of course once we go to wind for most of our electricity the only heat loss will be in the production of the parts. As I said we are coming right along in the electrical generation sector.
It turns out that our homes are relatively efficient. They make use of 75% of their input energy according to Department of Energy estimates. I would say this is a little high. I'd estimate that only 50% is effectively used but still the gains in this sector are not great. Supposedly the industrial sector makes effective use of 80% of it's energy input. This I can believe. Waste costs money. Waste reduces profits. Waste is an unexploited resource.
Now the actual number for industry may only be 60% but I believe where profit is involved people will spend money to save resources when the investment is profitable. For 200 or more years industry has become steadily more efficient in its use of resources. Mostly without government mandate. As new processes become cost effective they get implemented. Over time the least efficient fail. A brutal system but always improving.
So now we come to the transportation sector where the problems are biggest and while not without hope our immediate prospects are dimmest.
The gasoline engine like all heat engines wastes about two-thirds of it's power. Then you have other losses in transmission and road and tire friction so that only 20 per cent or less of the energy put into this sector actually delivers people and their goods to their destinations. Hybrid vehicles now coming into production will increase the efficiency to perhaps 30 to 40%.
(Editor's comment: From a well-to-wheel perspective, the best internal combustion engine is only 14% efficient overall while a modern diesel-hybrid has a well-to-wheel efficiency of 26%, according to GM).
The main advantage of the hydrogen economy is that transportation fuels can be made with wind tubines. Hydrogen fuel cells that do not require high temperatures to operate - the PEM type cells - are only about 40 to 45% efficient in turning hydrogen into electricity. This is not much improvement over the hybrid, if any.
The problem with high efficiency fuel cells in the range of 55 to 60% efficient is that they run at 1200 degrees Fahrenheit or hotter. Now there are better fuel cells available if we can deal with higher temperatures and reformers that change gasoline to hydrogen at 80% efficiency. This solves the fueling infrastructure for the time being so we have time too bring hydrogen to market.
But automobile engines are cheap. They can be had for $50 a KW, while current fuel cell technology is running $1,000 to $1,500 a KW. With autos needing a steady state power of 10 to 40 KW, the auto engine for a small car that would cost $500 if it ran on gasoline would cost $10,000 if it ran on hydrogen.
So fuel cell technology has quite a ways to go before it is competitive for automobiles. Instead, the first mobile application that is likely to see wide spread use will be tiny methanol powered fuel cells for cell phones and laptops. Here even a relatively low efficiency at a high cost would be an improvement over today's batteries. Expect to see these in stores in one to three years.
M. Simon is an industrial controls designer and Free Market Green
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