(This blog is a technical how to on how I created our solar powered food truck. I am not an expert, or professionally trained in anything other that being an environmentally conscious chef, and self taught food truck builder.)
I have tried to write this blog post so many times, but I always get bogged down in making it too complex. I have written countless drafts and re drafts, but none of them succeeded in really getting across exactly what I used and did to create our solar powered food truck. Each time I would hit a road block, wondering if what I had written was too patronizing, or too complicated, too boring or not detailed enough. So, this time, I’m not going overthink what you, as the reader might be looking for or second guess what the reader might already know. Im just going to write it all down. To be honest I have already written it down over 20 times in emails and Facebook messages, as a response to different people who read part 1 in this series and wanted to know more. A few days ago one guy named Mike told me “not worry too much about being overly technical, as the audience can always google more info.” He told me just to post exactly what I had sent to him, as the second blog in this series. After all, my aim is to help others create solar powered food trucks, not to write Shakespeare, so here goes!
What did I use?
Well, lets keep it simple, heres a list!
Hood vents –
Traditional commercial hood venting system running off AC power (I researched so much into this and it seems it is the one thing that does not exist in DC) this is 80% of my load but runs only 4hrs per day.
Solar panels –
Invensun 190Watt Mono-crystal Solar Panel x3 (I’m buying one more as we are opening 1 more day a week this summer)
Schneider / Xantrex HFS 2055 – 2000Watt Pure Sine Wave Inverter
What I use thats not electric that saves me power?… Another list!
iPad Air with a Square reader. No Printer. Whiteboard and pen to note down orders. I have never needed to charge the iPad during service- the battery lasts for days. I have a 12V cigarette lighter style outlet installed in case i do need to charge it. A receipt printer isn’t really necessary and the lack of paper contributes to our environmental efforts. We have a hand written receipt book (which I have never had to use) and can email receipts.
Hot water heater-
(Spark is provided by 2 D batteries so no power is needed)
(This is massive overkill for some, but as a dedicated pasta truck I need a range this big and powerful)
ITS $40 FROM WALMART LASTS ALL DAY AND IS LOUD ENOUGH FOR A FOOD TRUCK. THIS AIN’T A DANCE PARTY!!
How does all this will work-
The coolers run 24/7, but draw very little power as they are super insulated (6inches thick!!!) As they are chest style, opening them often does very little to effect the internal temperature.
The lights are used rarely as we operate mostly during the day. We are able to work under natural light most of the time. We built our food truck inside a bus, and as such there are plenty of big windows. Since we are not open in winter, and the days are long in summer here, If we do have to use the lights it is rarely for longer than 2 hours. We have never used all five lights at once, on their highest setting. They are far brighter than I imagined, and produce an impressive amount of light considering how little energy they use.
The water pump is only used when we turn on a tap, so doesn’t use much power. Just like electricity, the water on our truck is finite, so we don’t run taps for too long.
The biggest draw is the hood vent so our power needs were based on that. I contacted a food truck fitter and flat out asked for the stats on power usage for their hood vents.
How does the solar and battery storage work?
We have the 4 AGM batteries mounted in a case under one of our prep benches and have most of the other solar gadgets tucked away under benches or high on the rear wall so as to not take up much space.
Our system has 3 ways to be recharged. The 1st way, and method that we use 95% of the time, is from the 3 (soon to be 4) solar panels on our roof. We always try to park in full sun, and are careful to move the truck throughout the day on prep days, to follow the sun. Its important to make use of every hour of sunlight possible. We also ask for the sunniest spots possible when we are at farmers market’s so that we can catch all of those precious rays.
The second way we make power is through the use of a solenoid to the food trucks alternator. This charges the batteries whilst we drive. As we only travel a maximum of 40mins drive from our base, we don’t make a lot of power, but in that time we can gain up to 10% charge, and every little bit helps.
Finally, our failsafe method of battery charging is through a shore power cord. This ensures that even if it rains for a week straight, or if the smoke from forrest fires blocks out the sun, we can still charge up overnight each night and open each day without worry. Our system was sized to hold 3 days worth of power in the batteries, so with this we only require one out of three days to be sunny, or the chance to charge up from mains power twice a week. In reality it all depends on how busy the week was, where our locations were, and how much sun there is.
All in all after 1 summer open I can confidently say that it works! We had to charge up by mains power a few times, because we opened more days per week than we expected, or experienced unexpected sunlight shortages. To counter these issues, we are adding 1 more panel this year, in hopes that we can avoid the use of mains power at all. One more panel will help us to charge the batteries faster when we are closed. It will also help us to not deplete the batteries as fast when we are open, as our system will be simultaneously charging the batteries and depleting them. The more panels you have, the slower you will drain the batteries, and the less hours of sun you will need to top them back up.
So why did i choose these exact items???
You will notice that most of these pieces of equipment are DC powered, if this confuses you read my first blog. But the basic principal is batteries store in DC and it wastes a lot of energy to convert from DC to AC so the key it to avoid wasting the energy you are going to so much trouble to make.
Refrigeration- I chose to go for all Sundanzer DC household fridges and freezers and they work amazingly. They are designed to be used in off grid homesteading type applications and they hold up very well in commercial kitchens. After 6 months of rattling around in a food truck, they have (knock on wood) been faultless. I originally wanted to use Steca coolers as they have the best reviews worldwide from the homesteading crowd. They are so amazing because with just the turn of a dial you can change them from fridge to freezer, whereas with the Sundanzer the compressor is different so you do not have the option of changing your mind after purchase. I ended up going with the Sundanzers solely because they fit the dimensions better and they were more commonly available in North America. This means parts will be easier to find. This is important, as unlike with most commercial kitchen fridges there are no dedicated technicians I can call to fix them if they are malfunctioning. Luckily, they are designed very simply, so should be easy to repair for your average handyman.
Water pump- Whilst my fridges are from homesteading applications, I looked in another direction to find an appropriate water pump for my needs. This pump is actually intended for use on sail boats. In this particular instance the needs of a Food truck and a sail boat are surprisingly similar. Sailboat water pumps are designed to be run off of a battery bank, to withstand motion and intermittent use, and to be fixed, using minimal parts, in emergency situations by a non professional. I chose this pump in particular because Shurflo is a well known, quality brand, and every review I read online for their products was amazing. To figure out which pump I needed I looked into the flow rate of the taps that I was installing, and then chose a pump which was capable of producing a slightly faster flow rate than necessary. So far, it has also been perfect the whole time, however I am yet to see how it has fared surviving hibernation over a Canadian winter.
Whats next? Oh the F***ing hood vents… I spent so many nights researching DC powered, commercial strength hood vents and found nothing! I hope eventually to test a few DC fans and try to find the right combination to create my own DC option. My hood vents are 80% of my load, and in my eyes that can be reduced, making my power needs considerably smaller. If I ever figure out a solution to this, you can assume I will be posting a brand new blog all about how!
(If you have any ideas then email me at firstname.lastname@example.org ) In the absence of a better option, i am currently running a regular commercial hood vent. As previously mentioned, I rang the company I had found to install it, and asked for the the power draw. I essentially sized my system around these figures.
Lighting- For lighting i went with DC LED Fluorescent RV lights. I chose these after talking with an RV fitter, who told me these were the most energy efficient option and would provide ample light. Thats all the thought i put into it, really. As much as they work very well, and don’t use much power, I would prefer for them to not be fluorescent as it greatly affects the quality of my Instagram photos….lol.
Ok now the solar and battery stuff- For all of this I tried to research my options solo, and ended up finding a great operation called Canadian Energy to guide me. With the help of them, my self taught electrical knowledge and the figures I had worked out myself based on the equipment chosen, we were able to piece together a system to suit. One of the biggest decisions was what type of battery to use. With batteries, you get what you pay for but I’m not made of money so I had to decide if the positives were worth the cost. The main choice i had to make was between deep cycle lead acid golf cart style batteries or AGM (Absorbed Glass Mat) batteries. The biggest issue with Lead acid batteries is that they would have needed to be sealed from the interior of the food truck and vented to the outside. Once i figured out that i had nowhere on the outside or underside of the truck I could safely store them I was forced to discount them. The AGM batteries have a reported longer life, and do not release any harmful gases. As such they do not require venting or a sealed compartment. They are more costly, but I think I made the right choice as they are purposely built for the exact situation that they are in and were engineered to be used in a solar system un like golf cart batteries.
As for the solar panels we chose the highest performing panels that would fit on the roof of the truck utilizing the space as best as possible. I only bought 3 but had the wiring run for 4 as I always imagined that I might need to make the system larger if I had made any errors in my figures, or changed any piece of equipment on the truck.
As mentioned in the previous blog, these are just the solutions that I discovered to my own, specific truck set up and specifications, but I am very happy with the results, and sincerely hope that all of the time and effort I put into researching and creating this Solar Powered Food Truck might be of interest and of use to other aspiring food truck builders.