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What happened to all the solar thermal systems from 30-40 years ago?

Interceptor Member Posts: 46
I bought some old Solaron collectors from Fort Hays State University in Kansas. The person who was put in charge of selling them did not know much about the original system, but he did tell me that the system never worked properly because the building did not have enough load for the system. I can't find much more info about the installation, just a short story in the school's paper which said they had been removed so repairs could be made to the roof, and that they had not been operational for several years. There were 200 collectors offered for sale (I bought 20 of them) so this must have been large and expensive system. The building they were originally installed on (Rarick Hall) was built in 1981, I presume they were installed at that time. The people at Fort Hays provided a copy of the Solaron brochure with specs and installation guidelines dated 1979. On the front page there are pictures of two other installations, so I did some research on them.

US Post Office, Ridley Park PA. 2205 sf collector area for space heating and cooling. This building was completed in 1976. The building was featured in Kaiman Lee's Encyclopedia of energy-efficient building design: 391 practical case studies. The solar panels provided 20% of the post office's heating and cooling energy needs. They were removed in 1990 for unknown reason.

Navy Pier Administration Building, Chicago IL. 7344 sf collector area for space heating. This system was also featured in Kaiman Lee's Encyclopedia of energy-efficient building design and was in the planning stages when the book was printed. In 1977 the system cost $320,000. I cannot find any info about how long this system was operational, but looking at the building on Google Earth I do not see any collectors on the roof. I suspect they were removed during a $200 million renovation in the 1990s.  

So all this has me wondering, How many of these solar thermal systems from the 70's-80's are still operating, and what are the reasons for the ones that are not. I suspect  low fuel prices in the late 80's-90s put a lot of systems out of service. It doesn't seem like the collectors have changed much since then, maybe the control technology wasn't adequate? 


  • RJ_4
    RJ_4 Member Posts: 484

    I remember back in the mid 1970s congress passed the energy tax act which allowed home owners a 40% or more tax credit on solar system installs and additional 15% on insulating , not sure what tax credit was allowed for commercial installs,  this created an overnight appearance of solar companys, some legitimate some with non tested systems, the better systems still had the problem of storage when there was no sun. When President Reagan took office in the 1980s the tax act was dissolved. I remember solar companies going out of buisness with in days. The fact that some of these systems were never proven and that the life span of alot of solar hw panels is between 25-30 yrs may be the reason some of these old systems are being abandoned

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  • Kevin_in_Denver_2
    Kevin_in_Denver_2 Member Posts: 588
    Solaron panel was from "Radco"

    I was the design engineer for Solaron from 1981-1983.

    We were originally primarily an air panel manufacturer, but discovered, like everyone else, that liquid panels made more sense for the application that made the most sense, DHW.

    Anyway, the panels you have were sourced from a company called Radco, and they didn't have the best specs.

    I was hired to drag the company from draindown to drainback. By now, almost all of our draindown systems have failed, frozen or been removed because replacement parts are unavailable or too expensive, or the systems looked ugly on the roof.

    The drainback systems could still be running because those parts are available, and incorrect installations were rare. However, most homeowners eventually had them removed because they can't justify the cost of the repairs vs. their savings. Also, it was easy to get the system removed since Metro Man in Denver would gladly come get your equipment for free since about 1985, and still does it.

    I recently helped a guy fix his 1982 Solaron system. All he needed was a Taco pump cartidge, they still make practically the same pump. It was well under $200. It was easy for him to put in, and the system saves him an average of $25/month. But if a tech has to come and troubleshoot, the bill will run closer to $1000.....

    We started manufacturing our own panel in 1983, a much better design similar to the best at the time. Most US manufacturers still mimic it today.

    Very few of those huge systems were properly engineered, so they rarely worked right from the get-go, even with readily available maintenance techs at those institutions. Nowadays there is plenty of expertise to make large systems work, but the numbers are rarely compelling.

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  • Interceptor
    Interceptor Member Posts: 46

    Kevin, thanks for the info on Solaron, it's very interesting. The collectors I got had been reworked at least once in the past. It looks like the absorbers had copper flange fittings at the inlets/outlets and were bolted directly to the aluminum collector frame, which acted like a huge heat sink.  I don't know how that design ever made it to production. It looks like someone used a hole saw to cut the flanges off, then installed grommets to insulate the absorber from the frame. To think someone had the job of doing this to 200 collectors on a roof, And they would have had to remove the glass from every one to thread the fittings back in without twisting the internal header off.
  • Kevin_in_Denver_2
    Kevin_in_Denver_2 Member Posts: 588
    Murphy's Law

    Oh man what a pain that must have been.

    Here's a brochure on the SunSpool valve. It failed so reliably that it nearly bankrupted Solaron by 1981. http://shop.solardirect.com/pdf/water-heaters/valves/sunspool_brochure.pdf

    Solaron was founded by George Lof http://en.wikipedia.org/wiki/George_Lof

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  • jt3
    jt3 Member Posts: 31
    33 Years And Still Going


    Had an American Solar King system installed in 1982.  (Sears was handling them at the time.)  Two 4x8 panels on the roof of a 2½ story New England Colonial with a 12 pitch roof in southeastern MA.  Sepco Solar Tank in basement with a Taco 011

    circulator.  At the time I had a rental tank from Edison which was costing me about $50 per month between the rental and DHW.  Watched the figures pretty close for the first couple of years and my highest bill was about $20 in February.  Lowest was in the summer and about $3 or whatever the minimum was at that time. 

     About 4 years into it the installer came back and checked the tank.  Said there was a

    recall on some of them due to an insulation problem, mine was one of them, and

    the tank got replaced, no charge. 

    A few years ago the replacement tank was leaking so I replaced it with an 80 gallon dhw tank with an external heat exchanger.  (Too old to haul one of those Sepco tanks down to the cellar with a 6’ ceiling)  Electric not connected.  Solar tank feeds into an Amtrol 40 gallon indirect which brings the solar up to temperature if it isn’t hot enough. 

    System probably isn’t as efficient as it was when new but it still works.  Taco pump is

    still running.  Air bleeder was changed when I put in the 80 gallon tank.  Checked

    the expansion tank yesterday and realized that it needed replacing so that is

    on order.  Every 3 years the system gets drained and flushed with a garden hose until the water runs clear.  It then gets refilled with 6 gallons of Cryotec 100.  (what the installer used when they put the system in)

    My payoff on the system after rebates was just about 2 years.  The few people I’ve

    talked to over the years regarding solar say there was a lot of problems with the Solar King system.  Mine has actually been pretty good.  I’ve had to do some minor things over the years but nothing that wouldn’t be considered normal maintenance.  Can’t understand why more people don’t use them.  If I were younger and looking for a new house, I’d make sure the orientation was correct and cover the roof with PV panels. 

    Jim T.

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  • Interceptor
    Interceptor Member Posts: 46

    I started the thread mostly out of curiosity, but also partly because I wonder what my own system will be doing 30 years from now. It's helpful to see what mistakes have been made in the past so I don't repeat them. It seems like all of the really big systems are gone and only a small percentage of residential systems are still running. One advantage I have is that I will be able to do maintenance and repairs myself, for as long as I am physically able. Thanks again for the input. I wasn't around for the 1970's energy crisis (born in '76), I can only read about it.
  • Bob Gagnon plumbing and heating

    Connecting the panels to a heating load too. Harvesting low temperature btu's during the heating season will make the panels much more efficient.

    Thanks, Bob Gagnon
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • mark schofield
    mark schofield Member Posts: 153
    Grumman Sunstream

    Mine has been working since the late 70's. A new storage tank (electric water heater for storage only), one new pump, and a new Goldline controller. The panels and heat exchanger are still fine. 
  • hot_rod
    hot_rod Member Posts: 22,245
    Often times

    Perfectly fine, working systems are removed when a building needs re-roofing. Rarely do building owners want to re-mount 20 year old collectors on new roofing

    I too remove those old large systems for the parts. I've sold hundreds of used thermal collectors on Craigslist and via the want ads. DIYers love 100 dollar collectors
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Weezbo
    Weezbo Member Posts: 6,232
    edited December 2013

    I did not know that ..

    that is some mighty fine copper paint with the copper gutters by the way.



    looks like the sensor needed some camo..though.. *~//: )
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