A heating contractor can tell you if venting is a problem in your operation. Use Greenhouse Space Use only as much greenhouse space as needed. Space them out using more greenhouses as needed. Group Plants by Cold-Tolerance Use a thermometer and don't set temperatures higher than needed. Group crops with similar temperature requirements when possible.
Fuels burn differently and produce different amounts of heat.
To determine the Btu value per dollar, divide the fuel's Btu per unit by the unit price. Here are examples. At 80 cents per 100 cubic feet, natural gas gives 125,000 Btu's per dollar. At 6.2 cents per kWh, electricity gives 55,032 Btu's per dollar. It is possible to buy natural gas nationwide from the highest bidder, although it is probably easier for most growers to buy directly from the local utility.