1.) A typical coal-burning power plant can generate 200 megawatts (2.0 x 108 watts) of electric power.

a) In Columbus, some electricity is generated by burning methane gas generated by decomposing organic material in the city's landfill. If the methane plant can generate 2.5 megawatts of electricity, how many such methane-burning plants would be needed to replace one coal-burning plant?

b) In northwestern Ohio, a wind turbine can generate 1.8 MW of power. How many wind turbines would be needed to replace one coal-burning plant?

2.) Suppose you live in such a windy place that a windmill attached to your house can generate all your electricity.

a) Purchasing electricity from the electric company would cost you $600 per year. Maintaining your windmill costs $100 year. How much money do you save each year by using your windmill?

b) Suppose the windmill costs $5,000 to purchase and install. How many years must you use the windmill before you are paid back for the purchase and installation cost of the windmill?