“Coal has a bad reputation. People think all coal is ‘dirty,’ but

we have continued to improve in terms of lowering emissions. It’s

unfortunate that some people believe that the only way to solve our

environmental problems is to turn them all off.

“We’re using our coal fleet heavily because it’s cheap. We’re

trying to save people money, not poison them.”

Natural gas combined cycle: A growth area

“This is where we’ve added a lot of capacity. In 2005, we were reporting 177,000 MW and this year we’re up to 210,000,” said Hewson. (See

Table 6.)

There are some newcomers for 2006. For instance, No. 10, FPL

Group’s Manatee plant, used to be an oil plant; No. 13, Tenaska, was

No. 23 last year; and No. 20 McIntosh was just starting up in 2005.

“To make this list, capacity is what’s important—and it doesn’t

hurt to be in an area where you’re backing out gas steam plants or oil

steam plants,” said Hewson. That’s why there are so many plants on

the list from Florida, some of which actually started out as gas steam

plants that were retrofitted to more efficient combined cycle plants.

Massachusetts, New Jersey, California and Texas are all like this

—and then there’s Georgia, where Southern Co.’s Mcintosh plant is

located. “Georgia is just a growing place to be,” said Hewson.

“Overall, the capacity factor decreased from 2005 to 2006, from

Industry Report

35 percent to 32 percent, because we added so many new combined

cycle plants,” said Hewson. “That affects the overall dispatch. When

you add faster than the generation growth, you end up with lower capacity factors.” (See Table 7.)

Heat rate (see Table 8) is always controversial, “at least in my mind,”

said Hewson. Overall, the efficiency for all gas combined cycle plants is

8,600 Btu per kilowatt hour, but “when people do their modeling, they

often use numbers like 6,500,” said Hewson. “For planning, it would be

better to use efficiencies that we can actually achieve.”

Hewson explained that when we convert to gas, we’re not

lowering CO emissions by as much as we think, and the price of 2

gas is very sensitive to what the cost of that implication is. The price

of CO credits necessary to displace a coal unit with a gas combined 2

cycle unit, given the difference of fuel prices, is very high.

“It’s not a very efficient way of reducing CO emissions. Mother

2

Nature does a better job; when we plant trees, that’s roughly $2 to $5

a ton for CO removal. And if we’re trying to be efficient and take the 2

low hanging fruit, we get a lot more bang for our bucks by decreasing

methane emissions at landfills. Methane has 24 times the global

warming potential of CO .”

2

[The NOX and SO₂ rankings were omitted because of space limitations but are included in the online version of this article at elp.com. Previous reports are also available on the website in the archive section.]