Real World Examples of Solar PV and Swimming Pools
SOLAR PV and POOLS – non-Pooled Energy pool
Below are examples of a non-Pooled Energy pool in Coogee, with data taken during different weather over a single week. This data is derived from a third party, solar monitoring service for a home. The time-clocks for the operation of the pool are set to use electricity from the home’s solar PV panels.
Note:- The run-time of the small pool in this example is only 4.5 hours, whereas real-world running in summer is usually in the 8-11 hour range. You need to do this to turn the water in the pool over at least twice a day in summer. A typical 50,000 litre pool would quickly turn green and dirty with such short running times.
On the typical 109 days of sunshine a year in Sydney, the situation looks as follows, and there is adequate solar energy available to filter and chlorinate the pool:-
Following is a typical CLOUDY day. There is insufficient solar energy to power the pool, and the pool automatically operates from Grid energy.
Please note that the vertical scale below is only half the one in the previous graph.
Look now at a RAINY day on the same scale.
Sydney typically has 129 days of rain and overcast days each year. On either cloudy or rainy days, this pool is using (expensive) shoulder and peak power from the Grid since the solar generation is nowhere near enough to power the pool and the house. In this home, the pool would be much better run, all year round, using off-peak power at night. Running as it is on shoulder and peak Grid power on the 129 typical days of cloud and rain, would wipe out the savings on the 109 sunny days, about 3x over.
On the remaining 127 days of intermittent sun and cloud, the graph that looks like:-
While this looks like a break-even in energy terms, it isn’t in cost terms. Dips below the red line use shoulder and peak energy and that costs 2-4x as much as off-peak power, or about 3-5x Feed-In tariffs. So, every dip is worth 4x, every peak.
Pooled Energy’s free Solar Optimiser is designed to address this problem for you by running your pool equipment from PV solar generated power on sunny days, and from off-peak on rainy and overcast days. That way you save both energy and money. Overall, the Pooled Energy Solar Optimiser really makes a big difference to operating costs.
The fact that a Pooled Energy pool typically uses one-third the power of conventional pools for filtration and chlorination helps further, making solar easier and better to use.
SOLAR PV and POOLS – Pooled Energy pool
Below is a 3 month trend record from March to June 2018 of the net solar energy export to the Grid of a Pooled Energy customer with a small PV panel array, a large heated pool and a large house with air-conditioning. These records are from Pooled Energy’s Network Operating Centre system.
The pool equipment was operating at night times using Off Peak power for April, May and then daytimes during solar generation times, for the last month, June. This was done at the customer’s request. You can see that solar exports are minimal in winter, dropping to zero across many days
Net household Solar energy export to the Grid
For interest shown below is the Net household energy consumption excluding solar PV panel generation
Clearly, this customer is better off running the pool from off-peak power as he does not have enough solar generation to run the pool day-times. We have since, with the customer’s agreement, readjusted the schedule for the pool equipment to operate during the Off Peak period again. This customer’s solar generation is too little and his household consumption too much for the Solar Optimiser Software to be effective.
There are customers where utilising the electricity from their solar PV arrays to operate pool equipment is viable through the year, but others where the schedule needs to managed depending on the season. NOC monitoring gives us the ability to tell which is which.