I don't know if this will work for you, but I'm using a Hayward variable speed pool pump called Echostar. I've been running it 24/7 since installing it about 3 or 4 months ago. One of the things I like is being able to regulate the flow and therefore the electrical costs. Spec wise, it will pump approx. 150 gpm at 50' of head. I'm using 3" piping. Operating costs range from $10/month to $150/month depending on what rpm you decide to run. I'm only using half speed now for $30/month for approx. 80 gpm flow. The control panel will tell you how many watts you're using an hour, which is nice to compute electrical uses. As far as I know, these pumps were designed for running 24/7. This pump will also self prime to 10' of head, where many others will not. Something to consider. Here is a link to Hayward's site:
http://www.hayward-pool.com/prd/In-Groun...-1_14002__I.htmOnline cost somewhere around $850 if I'm remembering correctly.
