The way you are billed for power impacts how your savings for installing solar or wind are calculated. The 4 most common utility billing types are: General Service (Residential), General Service (Non-Residential), Demand, and Large General Service.
General Service (Residential & Non-Residential)
General Service is intended to recover the distribution and billing-related costs, which include having an electrical distribution system in place, plus the cost of the meter, servicing and reading the meter, mailing the bills and maintaining customer records.
With demand billing, the customer's electric bill is composed of two charges:
A base energy rate + a demand charge. Click here for a detailed explanation of how demand based billing works.
Large General Service
Large General Service charges typically include normal general service charges plus demand charges and a power factor charge.
Demand charges are a measure of the capacity or the rate at which you use energy. It represents the greatest amount of energy used in any 15-minute intervals during a billing cycle. Within a customer class, if two customers use the same amount of energy but one has a higher demand, the customer with higher demand will see higher bills.
Power factor charge measures the relationship between the amount of power used and the work done. A lower power factor percentage will result in an increase to your monthly demand charges.