By: Jack Colton
Customer: I'm thinking of building a food service truck. Can inverters supply enough power for essential equipment like refrigerators, freezers, and mixers?
Answer: For many years, Wagan has supplied power inverters for use in food trucks. There are some real advantages to using inverters instead of generator power because of pollution issues and cost of fuel.
A typical food truck is configured with its two refrigerators, microwave oven, surface burners, oven, and ventilation fan. Often, a hot dog cooker, hot water tank, and steam table are required. Sometimes a dough mixer and blender are aboard. Refrigerators, microwave ovens, and mixers are typically used for a brief time or automatically cycle on and off, so the demand is not constant.
Whenever possible, use propane for appliances that are constantly heating. These are hot water heater, surface burners, hot dog cooker, and deep fryers that operate from propane or liquefied natural gas (LNG).
Air-conditioning is difficult because of the high and frequent energy demand. Air conditioners about 1500 BTUs need 140 amps of DC if an inverter supplies power. There are a few basic principles that should be followed for best results. If you are starting from scratch:
1) Use propane for heating tasks like hot water tanks and ovens. Propane is much more efficient than engine generated electricity stored in batteries.
2) Install the largest alternator or a second alternator to provide at least 200 to 300 amps when the engine is idling. A local generator shop can help. Make sure they change pulley ratios to have the alternator spin faster at engine idle.
3) The installation will require several large, deep-cycle batteries. Make room for them and make sure they are vented to outside air. Flooded batteries (batteries with removable cell caps) release toxic and corrosive gases. The battery enclosure should be lined with materials that will not be attacked by corrosive battery gasses. Use a fan to force air through the battery box. Batteries should be located fairly close to the alternator and inverter to keep charging and inverter cables relatively short. Correct gauge cables are critical in keeping energy losses to a minimum.
Be sure to ask Wagan Customer Service to assist with your system configuration.