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I've been in solar hot water for 5 years with the Simple Drainback system. It's getting to the point where I know what I'm doing. Which means I have to move on to what I don't know how to do. And that is new construction with solar radiant with wood stove backup and sand bed storage. Banks turned me down for new construction last year, they didn't even want to consider new construction as appraised values were so low it made no sense to even try new construction. This has changed, and I'm now allowed to proceed.
The challenge in new construction is to be cost effective without going green, and doubly difficult when adding green elements to the mix. The new codes required fire sprinklers, and the entire structure must be engineered. And, water and sewer tap, impact fees and other soft costs are simply nuts.
Being a hot water guy, and seeing what I've seen, there is no doubt about my heating plan. I'm committed to solar thermal connecting to 16-24" sand bed storage plus an in-slab loop, with wood stove connection.
I'm selecting evacuated tubes, no doubt. I compared btu output of tubes against flat plates over the winter in Kansas, and under many different conditions. I also checked into the fable that tubes don't shed snow. There is no doubt that: 1) Tubes are vastly superior in generating low light, windy, cloudy winter energy. On a sunny day, at high noon, flat plates and tubes reach parity. The minute those conditions aren't met, or if a wind kicks up, tubes produce more heat, period. I can denominate this, should any wish to see the research. Regarding tubes and failure to shed snow: it turns out to be a function of where they are located and how they are racked. Snow shed isn't the issue, racking is.
I don't know a thing about wood stove/solar radiant production. I've done the work for others, and I hear love stories and warm fuzzy about the nice heat. I've felt the heat, and love the outcome. Sizing and construction of the wood stove loop is the hard part.
For the envelope, I'm using Faswall block. These are an ICU made of wood fiber, cement and coal ash, manufactured in Oregon so freight won't be high. The ICU system should provide a very tight envelope. For the solar radiant side, I'm using the 2' of collector for 10' of floor space 'rule of thumb'. For the wood stove coil, I'm looking at www.hilkoil.com. For the heat exchange system, I'm using the Simple Drainback system. That system costs $1,900. That's a load side heat exchange system that's perfect for radiant, very easy to install and operate. For tubes, I'm using SunTask SR-30's, these cost $900 per set of 30.
As for the production I can expect from the wood stove loop...this is a big question mark. My guess is I'll make 65-75% heating load with solar. Don't know what to expect from the wood stove loop.
The challenge in new construction is to be cost effective without going green, and doubly difficult when adding green elements to the mix. The new codes required fire sprinklers, and the entire structure must be engineered. And, water and sewer tap, impact fees and other soft costs are simply nuts.
Being a hot water guy, and seeing what I've seen, there is no doubt about my heating plan. I'm committed to solar thermal connecting to 16-24" sand bed storage plus an in-slab loop, with wood stove connection.
I'm selecting evacuated tubes, no doubt. I compared btu output of tubes against flat plates over the winter in Kansas, and under many different conditions. I also checked into the fable that tubes don't shed snow. There is no doubt that: 1) Tubes are vastly superior in generating low light, windy, cloudy winter energy. On a sunny day, at high noon, flat plates and tubes reach parity. The minute those conditions aren't met, or if a wind kicks up, tubes produce more heat, period. I can denominate this, should any wish to see the research. Regarding tubes and failure to shed snow: it turns out to be a function of where they are located and how they are racked. Snow shed isn't the issue, racking is.
I don't know a thing about wood stove/solar radiant production. I've done the work for others, and I hear love stories and warm fuzzy about the nice heat. I've felt the heat, and love the outcome. Sizing and construction of the wood stove loop is the hard part.
For the envelope, I'm using Faswall block. These are an ICU made of wood fiber, cement and coal ash, manufactured in Oregon so freight won't be high. The ICU system should provide a very tight envelope. For the solar radiant side, I'm using the 2' of collector for 10' of floor space 'rule of thumb'. For the wood stove coil, I'm looking at www.hilkoil.com. For the heat exchange system, I'm using the Simple Drainback system. That system costs $1,900. That's a load side heat exchange system that's perfect for radiant, very easy to install and operate. For tubes, I'm using SunTask SR-30's, these cost $900 per set of 30.
As for the production I can expect from the wood stove loop...this is a big question mark. My guess is I'll make 65-75% heating load with solar. Don't know what to expect from the wood stove loop.
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