Heliodyne panels, some approaching 30 years old. Closed loop glycol system with stainless plate heat exchangers, and PV pumped as a controller and a power source for the circ pump all in one. The hot water panels were attached to steel backframes, using "HelioClips" that slide into the edge extrution so no holes need to be drilled, while still on the ground, and then lifted with my boom truck into place. The back frames are strong enough to require the fewest roof penetrations possible, and those are steel pipe and standard roof jacks like your plumbing vents pass thru. They work equeally well for structural steel pipe as they do ABS pipe it turns out.
The 6 panel array feeds the shops radiant floor heat system, via the plate HX, no storage tank involved. All the heat goes into the 5" slab as soon as it's produced, and the exchange rate/pump rate is fast enough to keep the max temps low as possible, 100 or so, after realizing that at the end of the day you reap more BTU's making LOTS of warm weather then you do smaller amounts of cery hot water. I used to have a 500 gallon tank at my first place years ago, and I wouldn't heat the floor at all during the day, just try to get the 500 gallons hot as possible for night time use. IKeeping the loop temps low as possible, counter productive though it sounds, gathers a lot more BTU's. Especially when the final goal is largely rad floor space heating anyway, where 89-90 water is plenty hot enough.
The 3 panels on my small but very well insulated home work all year. A 120 gallon storage tank with a 3000 watt element halfway up, and a built in heat exchanger at the bottom is the first recipient of the hot water after it goes thru the plate HX. That way I heat 120 gallons of using solar, but when it's cloudy and the electric thermostat (set at 120) kicks on, I'm only heating 60 gallons. The tank has a timer, and I've found 4 to 6 pm for any possible needed backup heat works perfect for when I use most of my hot water domestically. I don't want to start a day that is going to be sunny, with a tank full of 120 degree water because the element just clicked off at 7:00 AM.
After the water goes thru the tank's heat exchanger, it passes by an aquastat that is set at 120 degrees, if the water is that hot, meaning my domestic tank is hot enough,a circ pump kicks and passes it thru another plate heat exchanger plumbed to the house radiant floor system. We get a lot of sun in the winter here, (when it's not snowing...) and at nearly 6,000' the sun is intense. A typical winter day may reach high 20's/mid 30's, and then upper teens to low 20's at night. The 3 panels will not only heat the entire 120 gallon tank up to 120 degrees (and hotter), but it also heats the house. It may be a tad on the cool side, air temp wise, first thing in the morning, but the floor itself is still warm, and if it looks like another sunny day, I'll just switch on a 750 watt radiant panel electric heater that's right by the snack bar where coffe is drunk etc. A smaller one in the bathroom assures I have a warm place to "go", no matter what, radiant heat beats hot air!
In the summer, when my production overcomes my usage, I flip a couple valves, unplug 1 circ pump and plug in another. The same aquastat, now set at 140, pumps water thru under ground insulated lines to my shop's 200 gallon home made stainless water tank 85' away. This keeps the home's 120 gallon from overheating, plus, as I have the main laundry room in the shop bathroom (big shop, small home) another pump exchanges water from the 200 gallon shop tank, to the shop's bathroom's 80 gallon tank, with it's built in HX. Suffice it to say I have plenty of hot water in the summer. It sounds more complicated then it is, actually it's MORE complicated then described, but I've built it up over the last 15 years, and had a similar system on other property for a few decades before that. Part two will cover the shop's wood boiler.
The 6 panel array feeds the shops radiant floor heat system, via the plate HX, no storage tank involved. All the heat goes into the 5" slab as soon as it's produced, and the exchange rate/pump rate is fast enough to keep the max temps low as possible, 100 or so, after realizing that at the end of the day you reap more BTU's making LOTS of warm weather then you do smaller amounts of cery hot water. I used to have a 500 gallon tank at my first place years ago, and I wouldn't heat the floor at all during the day, just try to get the 500 gallons hot as possible for night time use. IKeeping the loop temps low as possible, counter productive though it sounds, gathers a lot more BTU's. Especially when the final goal is largely rad floor space heating anyway, where 89-90 water is plenty hot enough.
The 3 panels on my small but very well insulated home work all year. A 120 gallon storage tank with a 3000 watt element halfway up, and a built in heat exchanger at the bottom is the first recipient of the hot water after it goes thru the plate HX. That way I heat 120 gallons of using solar, but when it's cloudy and the electric thermostat (set at 120) kicks on, I'm only heating 60 gallons. The tank has a timer, and I've found 4 to 6 pm for any possible needed backup heat works perfect for when I use most of my hot water domestically. I don't want to start a day that is going to be sunny, with a tank full of 120 degree water because the element just clicked off at 7:00 AM.
After the water goes thru the tank's heat exchanger, it passes by an aquastat that is set at 120 degrees, if the water is that hot, meaning my domestic tank is hot enough,a circ pump kicks and passes it thru another plate heat exchanger plumbed to the house radiant floor system. We get a lot of sun in the winter here, (when it's not snowing...) and at nearly 6,000' the sun is intense. A typical winter day may reach high 20's/mid 30's, and then upper teens to low 20's at night. The 3 panels will not only heat the entire 120 gallon tank up to 120 degrees (and hotter), but it also heats the house. It may be a tad on the cool side, air temp wise, first thing in the morning, but the floor itself is still warm, and if it looks like another sunny day, I'll just switch on a 750 watt radiant panel electric heater that's right by the snack bar where coffe is drunk etc. A smaller one in the bathroom assures I have a warm place to "go", no matter what, radiant heat beats hot air!
In the summer, when my production overcomes my usage, I flip a couple valves, unplug 1 circ pump and plug in another. The same aquastat, now set at 140, pumps water thru under ground insulated lines to my shop's 200 gallon home made stainless water tank 85' away. This keeps the home's 120 gallon from overheating, plus, as I have the main laundry room in the shop bathroom (big shop, small home) another pump exchanges water from the 200 gallon shop tank, to the shop's bathroom's 80 gallon tank, with it's built in HX. Suffice it to say I have plenty of hot water in the summer. It sounds more complicated then it is, actually it's MORE complicated then described, but I've built it up over the last 15 years, and had a similar system on other property for a few decades before that. Part two will cover the shop's wood boiler.