The short answer is: yes you can run your pool pump from solar panels, but one single solar panel likely won’t cut it.
Your pool pump is likely something that you don’t really think about, until something goes wrong with it. So you might not be aware of home much it’s quietly adding to your electric bill each month.
Lucklily, in most places where swimming pools are found, it’s also sunny. Unless you’re in Iceland of course where each town has a delightful geothermal pool.
Pool pumps can also run at pretty much any time of day, and still be effective at keeping your pool sparkling clean. Which means you can run them when the sun is shining.
Running your pool pump from solar seems like a no-brainer then, right?
How Much Electricity Does a Pool Pump Use?
To work out how many solar panels you need to run a pool pump, we have to first understand how much electricity we need.
A standard pool pump is typically 1½ to 2 hp and operates using a single-speed induction motor generating excessive filtration flow rates. This volume of water is achieved by a 3,450 rpm rate that requires between 1,500 and 2,500 watts of electricity depending on the service factor of the motor.
So 1.5 to 2.5 kW when your pool pump is running. Let’s say 2 kW on average. That means if it runs for 6 hours, it’ll use about 12 kWh of electricity per day.
Obviously the cost of that depends on what you pay the grid. Here in Spain it’s about €0.25, which works out as €1,095 per year (at the time of writing in Spring 2022).
In California, it would be $0.199 per kWh which works out as $871.62 per year.
How Can You Reduce the Amount of Electricity Your Pool Pump Uses?
Instead of going directly to switching your pool pump over to running on solar power, let’s first look at needing less energy to begin with.
The US NREL has done some great research on switching to a variable speed pool pump. Essentially, your pool pump is probably running at full speed the whole time, using a lot more power than it actually needs to clean your pool.
They found that by using a variable rate pool pump, typical use goes down from 12.6 kWh to just 2.2 kWh. “This is a savings of 10.4 kWh per day, or approximately 3,796 kWh per year.” (NREL)
Solar Power for 1.5 hp Pump – How Many Solar Panels Do You Need?
To produce 12 kWh of electricity per day, you’ll need a different number of solar panels in summer than in winter. So it depends if you want to run your pool all year round.
In Southern Spain
In Almeria, Southern Spain you would need 3.5 kW of solar panels to produce 12 kWh per day, all year round. That’s 9 solar panels if you’re using modern (but not top of the line) 385w panels.
If you only want to run your pool pump from April to September (when there’s a lot more sun), then you could get away with a 2.7 kW system, or 7 solar panels.
If you switch over to a variable pool pump, then you’d only need 2 solar panels to run your pool pump all year round.
In California
In Los Angeles, California you would need 3 kW of solar panels to produce 12 kWh a day through the seasons. That’s 8 x 385w solar panels.
For summer only (April to Sept) then you could have roughly 2.4 kW of total solar power, or 6 solar panels.
And if you were to switch over to a variable speed pool pump, you’d only need 2 solar panels to run your pool pump all year.
These numbers apply to grid tie systems, where you’re using solar to offset the electric consumption, in this case your pool pump.
If you’re looking to build an off grid system for your pool pump, then you’ll need to factor in extra solar panels plus battery storage, to make sure you’re able to have some power in reserve for dark days.
What About Heating Your Pool With Solar?
Heating your swimming pool can be quite expensive, so heating it with solar energy can be an attractive option.
There are three main ways to heat your pool with solar:
- Powering your existing electric pool heating system with solar photovoltaic panels.
This is the least efficient but if you already have an electric pool heater, and you’re considering adding solar panels to your home, then it’s the simplest way to go. - Solar thermal panels
These panels capture the heat of the sun directly and then via a closed loop of liquid, transfer heat to the water pipes that are re-circulating your pool water. This is 2-3x more efficient than using PV solar panels to power an electric heater. - Running a swimming pool heat pump from solar PV
This is a much more efficient option that using a standard electric pool heater. A swimming pool heat pump draws in additional heat from the outside air, or the ground. Read more here.
