Solar System Design and Consulting form Summit Solar Systems.

It's pretty straight forward when you look at the difference between Photovoltaic and Hydronic approaches:

The Photovoltaic approach is only to make electricity. In most cases only a percentage of the electricity you produce goes towards your electric bill unless you own the panels on your house. If you own the panels on your house, you're payback on the system will most likely will outlive you because of the cost of the system, and the amount of electric energy used each month.

The Hydronic approach is more complicated at first glance, and should be designed into the project as early as possible however, there are so many different applications and designs that can be augmented to existing heating systems down the road that it always makes sense to review an application post building. In addition the payback is much faster on a Hydronic system no matter what the size.

How Affordable is Solar? More than you would think and Hydronic Solar has the best ROI of all

Here are some other advantages to Hydronic Solar that really makes it a no brainer which type of system to install:

Benefits - Green, inexpensive heat, off the grid, flexible, easy to install.
Disadvantages - The panels are visible in most cases.
Costs - Affordable, and compared to a standard heating system it's less expensive.
Savings. Monthly, yearly, five-year - My system pay back was 6 ½ years based on the price of Oil in 2005.
Maintenance - check the PH levels every 10 years on the closed system side.

A couple other considerations that make Hydronic Solar the clear winner:

What is the life span of the Hydronic Panels? Do they damage from hail, snow, ice, or wind? Hydronic Panels are designed to last 80 years and beyond. Snow and ice slide right off of them, and when mounted correctly they can withstand wind gusts over 200 mph.
How difficult are the panels to replace? How can you tell if one panel is defective? Always check your system pressure first. This should be in the 15 to 18 PSI range. Each array is segmented to no more than 8 panels so that array can simply be isolated for repairs if you have multiple arrays. To replace an entire panel is simply a plumbing job of un-soldering the panel or repairing it on site. I have had my panels for more than 8 years now without a single issue. Each array when properly installed will have shutoff valves and a drain for such maintenance.

Read on: Information about My Solar Installation at the Summit

Solar Design: Hydronic Vs. Photovoltiac. Which is Better?