In their interesting article on the electric infrastructure, Clark Gellings and Kurt Yeager got most of it right. However, in 1879, three years before Thomas Edison’s Pearl Street Station, the first electric company opened in San Francisco. It provided electric energy to arc-light customers.
Edison did his best to prevent the commercialization of alternating current. Through an agent, he staged cruel public demonstrations electrocuting dogs, cats, horses, and even an elephant, to show that AC was unsafe. He even purchased AC apparatus to construct the first electric chair at Auburn Prison in New York. It was Nicola Tesla’s polyphase AC, promoted by George Westinghouse, that made possible the large transmission systems of today. Edison’s direct-current systems were largely obsolete by 1940.
Over the past 100 years, efficiencies of generators have steadily increased because of scale economies. 1 The efficiency of Edison’s generators in 1882 was estimated to be only 8%. It took the building of transmission lines and the increase in unit sizes up to 500 000 kW or more over 70 years to boost the efficiency to 38% for coal-fired steam turbines.
These economies could only have been realized by connecting giant generating stations to thousands of small loads over a very wide area, using transmission lines to reach substations at many load centers and then distribution lines between the substations and the small loads. The principal reason for constructing and operating transmission systems is to permit the use of giant generators, which are more efficient in converting coal to electricity, use far less fuel per kilowatt, and have far lower costs per kilowatt of generating capacity.
Now, however, the relatively tiny 250-kW molten-carbonate fuel cell is more efficient than even the largest central station, particularly when transmission and distribution losses are taken into account and the high price of natural gas relative to coal makes gas no longer as useful for generating base-load energy. Base-load generators, which are on line most of the time, have the more expensive generating capacity per kilowatt but have the lowest fuel costs per kilowatt hour. Even though they constitute only about 40% of all generating capacity, they supply 80% or more of all kilowatt hours. Intermediate and peaking generators that use more fuel per kWh supply the remainder when the base-load generators are being fully used.
With mass production, fuel cells’ hardware cost will drop dramatically, perhaps 20% with each doubling of production, and the full fuel-cell energy cost—including the costs of both fuel and hardware—will become competitive with that of central-station power from the grid.
Moreover, apart from their cost advantages, fuel cells can provide highly reliable power. They can cut toxic pollution emissions by some 99% and greenhouse gases by a lower percentage, and can do away with the transmission lines snaking through wilderness or through Connecticut suburbs.
The fuel cost of electric power from giant central stations has been so low over the past 100 years that, even after paying all the costs of transmission and distribution, central-station power has been the most economical. With the advent of the fuel cell, that fuel-efficiency advantage of large central stations over small ones has disappeared. The costs of new transmission and distribution that are necessary if large central stations remain the source of power are skyrocketing—from an average of $500 per kilowatt cost of all those currently installed to about $1500 per kilowatt for those installed in the last few years before control of transmission no longer gave control of the market.
I think that distributed generation with fuel cells will likely be the direction that our power supply will take for the future.
