Are solar panels worth having to heat a pool.

Photovoltaic panels certainly are great for running a pool pump.  I would think the only method you could use directly with them for heating would be a heat pump system.  A purely electrical element heater is going to be a massive drain.  You could certainly run the water from the pump through solar hot water collectors (or simply a long run of black pvc tubing) but it would need to be a good size to heat a regular sized pool more than a few degrees.

You would also need to fit a decent pool cover to use overnight, to retain any extra heat generated during the day.

We have a sliding aluminium/perspex pool cover. In mid winter, our pool was 9-10 degrees warmer than our neighbour's exposed pool.

Last November we had solar panels installed (32 square metres and a 6kw inverter). 

In late February this year we had a pool heat pump installed.

The heat pump worked hard in February and all of March. By mid April the pool was at 28 degrees. By May the pool was at 32-ish degrees and the heater is now barely running at all. 

Since installing the solar panels and the pool heater, our electricity bills have residualised to just the standing charges, metering charges etc.

I suspect that half the benefit of the pool heating is provided by the pool cover. Without it, the heat pump would be running much, much more.

Quite right, or you will just loose heat.  I have used a long black tube all over the roof to heat the water for years.  The solar cover also acts as a heater.

Be careful to stir the water up before you jump in.  The top 18ins (or 500mm if you prefer it) or so gets very hot.

There are solar panels specifically made to heat pools. They work at a much lower temperatures than domestic ones.

I have solar panels and an air source pump back in the uk definitely worth having in my opinion if you put the heater on a timer and only heat the pool at night it would be pretty much for free if you get enough panels.

Where is the primary heat source going to come from for a heat pump at night?  The last thing you need to be doing is paying for electricity,  even on Spain's longer night-time tariff.

Sun is free in the daytime, just get proper solar panels.

Sorry typo 

Only heat the pool in the day time not at night and the solar panels can run the air source heat pump for next to nothing.you will probably lose 1-3 degrees overnight depending on how warm the pool is.

You are forgiven, no one's exempt!!.

I still recommend the bubble wrap cover whenever you are not using the pool.

Mine just winds up onto a roller. It conserves the heat.