[strider3700]

This is actually pretty complicated to figure out.

First on pure energy use if the sun is shinning strong enough to make decent electricity with the PV it's going to be strong enough that you could more easily make hot water. So hot water is your better bet.

Now the question comes on finances. Normally hotwater tends to be cheaper to purchase and install, but that isn't always the case. Ontario also has/had an amazing program giving you really really good rates for electricity you generate and sell to the grid. It could very well be that the best financial move for you is to install PV and sell the energy you don't use to the grid using the profit to also install hotwater leaving more electricity to sell back.

It all depends on your installed costs and the current incentive rate. It used to be 70 cents/kwh for a grid tied roof mounted PV system. I believe they've reduced that now but it's still quite good.

I forgot to point out that both of these systems could be pointless if you don't get enough sun in your install location. Hit builditsolar.com and find the site assessment chart. Do that for your preferred install location and figure out how badly things are going to be shaded. Then find the section where you can look up your areas expected climate/cloud coverage and figure out how many hours of good sunshine you can expect. From there you can make a reasonable estimate on payback periods of various things.