The typical solar panels found on most food trucks in the United States range from 100 watts to 160 watts. But as long as it can produce about 30 AH of battery charge between 5-9 hours of sun exposure, a food truck can use it to substitute power and electricity needs. To properly estimate the number of solar panels needed to power a food truck, here are a few factors to consider and analyze.
4 Factors That Determine How Many Solar Panels a Food Truck Requires?
1. Truck Utility Load
When sizing the utility load for a food truck, there are certain calculations to be made. The maximum overall power requirements of all electrical appliances that will be used at the same time will be analyzed and efficiently determined.
You can always find most appliance values on the appliance stamp or tag nameplate. The appliance user manual will also provide the starting and running wattage, voltage, and current in amps. However, note that starting surge amps is entirely different from running amps and allowance needs to be made. Typical electrical calculations can be made using: watts = volts x amps and amps = watts/volts.
Notably, in food trucks propane is used for most cooking with grills, griddles, ovens and stoves. So propane-fuelled appliances are not expected to add directly to the electrical load, but indirectly they can add to the cooling load for the fans and AC. Also, hot water can be provided by propane, natural gas or solar hot water heaters, adding to the utility load. Refrigerators also present a continuous load and the air conditioning system is more or less the biggest.
Have it in mind that air conditioning unit energy demands make solar powering a food truck challenging. Howbeit, having proper exhaust fans and enough of them placed at the right locations to remove heat from propane cooking is the design issue that can help male solar powering easy and affordable. Heat shields and air windows can also help with limiting heat build-up and reflection of heat to be removed.
2. Food Menu
Have it in mind also that some menu concepts require less energy than others so the menu of a food truck plays a key role in determining how many panels will be required to generate adequate electricity. For instance, a coffee truck needs a lot of electricity to power.
An 18-foot gourmet food truck operating for 6 hours a day could function completely on solar power, using propane for cooking. However, this does not imply that any two food trucks of similar or less size will use the same solar energy.
3. Solar Panel Module
Photovoltaic modules come in various sizes based on the wattage, voltage and efficiency of the module. Note that power modules for utility application have higher efficiencies and are physically larger modules than battery charging modules. Consideration needs to be given to mounting the modules flat, tilted or extended.
Flat have proven to show better alignment in the direction of the sun, but generally gives less production. Tilted or extended modules may reach beyond the roof size and need to be aligned with the sun, which affects how the food truck is parked. Tilting and extending can add up to 30 percent more production.
However, modules come in efficiencies from 13 to 21 percent, with most utility modules averaging around 17. There are many physical sizes, from 1 foot square to 3.5 feet wide by 6 feet long. Each produces various outputs in watts, voltage and current. The watts per square foot can be determined for each module from manufacturer’s specifications and range from 12 to 18 watts/sq ft.
The roof area of the food truck may contain exhaust fans, skylights, air conditioning and other equipment that will take up space. Most of these items are 1.5 to 2 feet wide for an area of 2.25 sq ft and 4 sq ft used. After subtracting the roof-mounted items, the size of useful area for photovoltaic modules can be calculated.
Also note that the number of solar panels needed to run a food truck will depend on how many batteries the truck needs to keep charged. Note that you will need to add up the Total Amp Hours (AH) the batteries are capable of holding. The more AH a truck have, the more solar panels the truck will need.
For instance, if a truck has a single 12 volt battery, at about 100 AH, it will require about 300 watts of solar panels, minimum. With two 12 volts batteries or two 6 volts batteries, with around 200-250 AH, a truck will require at least 600 watts of solar panels. If a truck has four 12 volt batteries, or four 6 volts batteries, with around 400-600 AH, the truck will require around 1,200 watts of solar panels, minimum.
Owing to the above factors which can vary greatly across board, the exact amount of solar panels required by a food truck can be hard to estimate.
For many food truck operators, solar is a cost-effective source of power. An average food truck owner operating on a traditional generator spends a minimum of $5 to $10 daily on fuel. There is also cost, labor and hassles of maintaining a generator.
And the cost of replacement or repairing generators down the line can be higher than installing solar panels. Note that for a food truck operating 50 hours a week, the time for pay back can be as short as 9 months. The majority of food trucks operate on a diesel or gasoline generator that is specifically designed to run only a few hours.
Operators tend to run them at a stretch for up to 14 hours, resulting in a high output of greenhouse-gases, particulate matter, nitrous oxide, carbon monoxide and of course noise. Owing to the harmful effects of generators, and the way solar power can help offset operating costs, it is not difficult to see why food trucks are tending towards solar.