Fuel Cell Performance

> In the real world peak energy demand, and price, occur at mid-day
> due to air conditioning loads. Solar cells are ideally suited to
> meeting this peak demand, since they produce energy at exactly the
> right time. If peak loads can be handled by solar cells, then
> there is significantly less need for centralized power plants.

Not quite accurate. There would be significantly less demand from
centralized power plants but you'd still need all of those power
plants and you'd need them to be able to handle *all* of the demand
capacity. When it is cloudy the solar arrays will be less efficient
and the demand will come back to the central power plants. The
problem is even worse with wind turbines because there is no neat
correlation with demand as there is with solar power.

The utilities have to maintain spinning reserve that is ready to
engage at a moment's notice when the demand suddenly spikes. This is
expensive to maintain. Have you ever taken a shower and had someone
flush the toilet on you. That hot water gets diluted. The same
principle applies to the electric grid and the frequency of the
power must be maintained. With solar and wind intermittancy issues,
a utility can't rely on solar/wind performance for it plays havoc
with frequencies and load balancing. Up to a point the system has
flexability, but too heavy a reliance on wind/solar will actually
increase the risk of blackouts for loads will have to be shed to
certain areas in order to insure the frequency is within range for
the other parts of the utility grid.

Solar/wind only make sense when they can produce power for less than
the cost of the fuel used by the central plants. Then the economic
question becomes one of marginal cost with respect to starting the
plant. The capital equipment must still be payed for.

TangoMan