Yeh, we have high cost power down here too. If the pump is at end of life, it's a great time to upgrade.
I asked because 3/4 HP and 1.5" pipe is a good match and much better than many pools built on the old-school 1.5/1.5 (HP pump/pipe size) which was simple but pushing too much water for the size of pipe. With a 2 speed or VS, you'll probably be able to move roughly half as much water with 1/4 the power, so in very rough terms, 150 watts for twice the time vs. 600 watts at your current pump run time. If your electricity usage rate (i.e. not including fixed service charge) is $0.20 per kWh, that would save you around $175 a year. If your marginal cost is $0.25, that grows to $219 a year. Both assuming the same amount of water moved. I found California usage rates at an average of $0.15 per kWh, but I suppose this varies all over the place.
Pressure cleaners use a fair bit of power, so a different cleaner might be a cost-saving option worth considering as well. I'll bet you already have your pump run time optimized, but if not, there's good resources here for that determination as well.
If you want better/faster skimming or if there's algae spots showing up due to poor circulation, then you should consider higher HP for the new pump. If all is well, then you could consider one of the lower cost VS pumps that max out at around 1 or 1.2 HP. There's some great information here at TFP that suggests that a 2-speed pump is likely to be your most economic option, and it may be possible to upgrade your existing pump at quite low cost. That said, I kinda like tweaking my VS pump, so I'm all for it and if pump HP is high for the pipe, you can always turn it down
All depends on your objectives, and the experts here will give the best recommendation with your objectives in mind.