The Next Big Solar Movement: Solar Thermal Heating & Cooling Systems

Residential solar PV Over the last few years, the solar industry has enjoyed some great successes, despite some companies failing and others simply throwing in the towel. Not only have the cost of solar panels dropped dramatically (51% since Q1 2011, according to the Solar Energy Industries Association), but the average cost of a completed photovoltaic (PV) system has dropped by 33%. Utility and residential solar energy installations have also increased in number. In fact, there was 98 megawatts (MW) of residential installations in the second quarter of 2012 alone, which is up 42% from Q2 2011 installations (www.seia.org). 
 
As with any industry, there will be ebbs and flows, successes and failures. But, solar power seems destined to join other energy sources as a major contributor to renewable energy production and, as a result, supply is straining to fully meet this demand. Point-of-use generation to attain the bulk of our energy needs of a home or facility makes sense now more than ever before.
 
The photovoltaic industry has already established a strong foothold in the market, and is on its way to becoming even more mainstream. It has successfully reduced the cost-per-watt installed to a fraction of what it was 10 years ago—every year of late, it’s been breaking the annual installed kilowatt (kW) record from the previous year, even in this poor economic climate. Undoubtedly, the PV sector will continue to grow. So, where does the next opportunity in solar energy lie? How do we increase point-of-use generation? The answer lies in solar thermal, heating, and cooling.
 
Solar Thermal Technology
Solar thermal technology has always been unanimously considered the low hanging fruit of the solar industry. Unfortunately, it just hasn’t been all that popular. What’s likely held this segment of the solar industry back is the fact that heating domestic hot water (DHW) just isn’t as enticing as producing electricity. DHW is something we all take for granted. And, it’s a very small percentage of the overall carbon footprint of any household or facility in comparison to an electric carbon footprint. 
 
However, it’s a proven technology and a bargain per converted kilowatt produced, particularly compared to PV. The collector’s technology has pretty much been perfected, and it’s quite cost-effective for heating hot water—once the system has been designed. 
 
DHW is more inherently more complicated to install than PV projects. Requiring not just collectors, racking, and inverters like electric generating solar collectors, solar thermal technology also needs piping, pumps, electronic components, storage, and back-up equipment for those bad weather days when it’s necessary to make up for any over-demand on the systems. All of this further requires precise designing skills for an ideal, cost-effective system. System design can be challenging, and a lot of work considering all that it will be producing is hot water. It’s also only reducing about 10% to 15% of the overall carbon emissions of a structure. 
 
Where one large PV project can do the trick from an electricity standpoint, DHW often requires multiple residential or commercial projects to earn the same profits. Certainly, it’s a greater payoff per kilowatt produced, however, system design has to be factored into the cost equation. 
 
Meeting Future Needs
That being said, it’s worth starting somewhere if true change is to occur in terms of becoming less reliant on non-renewable technologies. To meet a growing interest in solar thermal, new technologies are beginning to hit the market that meet approximately 60% of most structures needs. In a recent article written by Herman K Trabish, he stated that the combined heating, cooling, and industrial processing possibilities of annual production—once fully developed—could reach five billion megawatt-per-hour yearly, and this doesn’t include the potential to produce electricity. Yes, solar thermal technology also has the capability to produce electricity. Combined, this is actually a larger piece of the carbon footprint than the electrical demand. 
 
The sleepy, DHW segment is just beginning to re-emerge and will generate even more jobs than its sister PV technology simply because of its complexity, and all the components required for proper production. It’s currently re-organizing on state and federal levels, as well as internationally, through associations such as the Solar Energy Industries Association (www.seia.org).
 
Equipment is being developed to deliver heating and even cooling to buildings. De-humidification units for commercial applications and industrial processing uses are also being manufactured at an affordable price points. Once demand for these products becomes more widespread, installed costs will drop even further. Several new pump manufacturing companies are also developing new products that consume about one-quarter of the energy of their previous models to further reduce the parasitic energy loads. Even PV is beginning to be incorporated in these systems to meet the additional electric loads requirements. The opportunity is a mega-billion dollar annual industry, and the world will be a better place because of it. 
 
 
Steve Elkin is the CEO of SolarUS, Inc.
 
SolarUS, Inc.
www.solarusmfg.com

Author: Steve Elkin
Volume: November/December 2012