Calculating heat rates in ERCOT, wholesale power prices in ERCOT

If I wish to determine wholesale cost of power, $/MWH in ERCOT, per zone, I know that (in general) the equation would be Gas price X Heat Rate = Power price
Example: Jan 2010 Power, $/mmbtu; NYMEX Jan. gas $/mmbtu X Heat Rate = $/MWH. ( for Jan. 2010)
The question is, what heat rate would one use? mainly, how would Heat Rate be calculated and what benchmarks would be used? Reuters, ICAP, ICE, Platts? And how does one calculate the price for each zone in ERCOT?

 

I assume there are different heat rates for each zone, on and off peak?

 

Ice has North zone heat rates on the screen now. Gas used is henry.

 

awesome

so that would be henry hub per month and of course ICE heat rate for each month? per zone

 

Right now only NZ I think. Its dollar for dollar on the spread. They take they anchor price of one (HH gas for instance), derive a power price based on HH and the HR, come up with the notional value, and give you an equal amount of each. To be exact, the gas amounts can be in 2 tickets.