This was my plan made from foam and nails.

It is to scale and moves so I could work out where to make it pivot.

It has a remote control to open and close, with another button inside the spa. Runs on 12 volt car battery so can still operate if the power goes off.
Solar panels on the roof heat the pool, water is pumped through panels using a dishwasher pump and a hot water thermostat.
This photo show the temp solar panel made from 13mm irrigation pipe.

Before with manual lifter.

Spa lifter finished.

The lid can be stopped in any position, so it acts as a roof when it is raining. Still have to finish off the stand for the panels and fit PLC to control water temp.
Here is a link to video of it working.....
[youtube]http://youtu.be/s3X6J4GGMyI


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