Short answer; YES! Long answer, it’s complicated.. Lets not waste any more time and take a closer look at what options you have for running your system completely or partially on solar power, or maybe just a good backup solution for when the grid falls out.
This can become advanced if you have no previous experience, but I will help you get through, and in the end you will know much more about solar and if you can run your system on solar power. So grab a piece of paper and a pen, you are going to need to take a few notes along the way..
How many kW do I use or need?
If you don’t know how many kW you use daily, I would like you to figure it out now. This is useful not only for aquaponics but also for hydroponics, aquaculture, aeroponics, and even your whole house if you really want to.
Step 1: Gather power usage information
Below I have linked an article that includes a calculator for figuring out your daily energy needs, and the result given is in kW (kilo-watt). Kilo means 1000 so 2kW = 2000Watt. When you open the link below, add your items to the calculator list and hit calculate button, make a note about your daily kW usage as you need it soon. Here is the calculator or click the image below now, and come back when you’re done. Don’t forget to note down your kW usage!
What is a photovoltaic/solar panel?
When the sun shines, we are showered with photons(light particles, that is also a wave), every day the earth is showered in more light particles than we can use, the problem is catching them and making them do work, this is where photovoltaic or more commonly known as solar panels come in.
Ruffly explained: A photon hits the solar panel and it creates electricity. If you want to know a bit more about how it actually works, read the next paragraph “nerd alert”, if not just jump over it as it might give you nightmares.
NERD ALERT: A solar panel consists of many solar cells, each of these cells is created by different layers of semi-conducting material that have one goal; each time a photon hits it, an electron is put into motion. The electron has no way to go other than into the collector placed above the cell, often seen as a mesh covering the surface of the solar cell, silver is often used for this as it is an excellent conductor with low resistance and can therefor be thinner making more room for photons to hit the actual semiconductor element i.e. making the cell more efficient, the electron goes through the load and reenters the solar cell collector below, the work is done and the power has been harvested into your load or battery bank. Tell me if you get nightmares about this tonight in the comments below..
Battery backup, why?
If you are off-grid this is a no-brainer, there is no power when the sun don’t shine. This includes night time, cloudy- , rainy- , snowy- and foggy days, even partially shaded panels can put a halt on your production. You might have grid power to back you up when the production is low, but what happens if the grid goes down too? Then there is nothing, no power. (Felt like a real doomsday prepper writing this 😂)
But fear not, I have written more about batteries and backup power here: (not done yet, it needs an overhaul of proportions)
How do you size a solar system to fit your needs?
Before you continue, did you use the calculator above and write down how many kW you use each day? If not, do it now. Continuing: Now that you have completed the calculation about your daily needs and have a number of kW you need we can get into the next phase of calculations.. I spent many hours to create this tool, so I hope you find it easy to use and that it gives you the answer you are looking for. If not leave a comment with your grief about it below.. 😉
How to use the calculator
- To get the best possible estimate, you need to choose your location or the closest city to you.
- Fill in your power usage per day (from the previous step)
- Now how many days of backup do you need? I would suggest 1-2 days if you are connected to grid, or more if you are off-grid. You can change this value and run the calculation again to see the difference. You can also put 0 here for not using a battery backup.
- Battery type: Choosing the battery type will affect the number of solar panels needed and the size of the battery pack. Lead acid might seem like the cheapest option, but it is not. You will need a much bigger battery pack, more solar panels, and they have much lower cycles/life time. In comparison LiFePO4 can last you >10 years if you don’t mistreat them (see the article about backup power linked above)
- Days to fully charge: How many days can you wait for the system to fully charge? If your system can charge 1kW per day, but you use 0,5kW daily, there is only 0.5kw available to charge the pack. If your battery is 2kW, it would take 4 days to fully charge.
- Press “Calculate” button and you will get a result. It will suggest a battery pack size in kW, and solar panel system in Watts, this is editable for a reason.
- You will get a table showing a lot of data, don’t worry it’s not hard to understand, you don’t need to worry about every field either.
- What is important is the last row of data, there you have an estimate of surplus power each month, this should not reach 0 or go into minus for an off-grid system, if you are on grid it does not matter too much. Anything above 0 is a good thing. If you are grid-tie you will sell the surplus when you have it, and buy when you are below.
- Adjust the solar panel size and click recalculate, this will update the table with new results.
Step 2: Calculate solar panel and battery pack size
Solar System Calculator
*: Enter the total kW used by your system on a daily basis, use this calculator if you need help with this.
**: If the sun don’t shine, how many days of power do you need? I would suggest 2-4 days for most people, but your environment must be taken into consideration.
***: Depending on the battery type you choose, the solar panel size and battery size will change taking DOD(recommended max dept of discharge) into account. Lead acid can be cheaper to buy but require more solar panels, compared to life expectancy LiFePO4 is cheaper overall, it also needs less solar panels. I would not reccomend lithium because of the fire hazard, at least not inside my house, but lithium can be found cheaper now as used battery packs from electric cars.
****: Days to fully charge is how long you can wait for your system to fully charge your batterypack, while also powering your daily needs. I would suggest 1-3 days.
Future add-ons coming:
Step 3: Completing the list of parts needed
Step 4: Finding a supplier(s)
Step 5: Install
Step 6: Grow food using the sun!