The solar hot water capstone project proposes that Alabama mandate the installation of solar hot water systems on new subsidized housing and HUD homes. The policy would be enacted through changes to the building codes and enforced during construction. The intent of the policy is to increase renewable energy, reduce greenhouse gas emissions, improve the renewable energy industry in the State, and reduce the utility bills for the poor. Other nations and have enacted regulations or building codes to require solar hot water such as British Columbia, Spain, Israel, Germany, Italy, Ireland, and Portugal (SolarBC, 2013). While Israel appears to be the policy innovator with policy in place since 1980, we will continue our European vacation with another sailor’s view of the world. Early last spring, a sailor boarded a ship in Lisbon, Portugal. The ship sailed south to Rota, Spain. A cold driving rain drenched the sailor as the ship pulled into the lee of the harbor. Several local houses had solar thermal panels installed which made perfect sense with the normally sunny weather in Spain. What was not obvious to the sailor was the policy that directed solar thermal hot water with new homes.
Spain provides an interesting case study in solar thermal hot water policy. Barcelona was the first Spanish municipality to require solar hot water to cover a percent of the hot water demands in new construction and significant refurbishments with their policy that went into effect in August 2000. The Barcelona mandate produced tangible results with an approved surface area of 31,050 m2 (21.7 MWth capacity) by December 2005. This represents an energy saving of over 25.000 MWh/year, and will reduce carbon emissions by over 4,300 tons of CO2 equivalent emissions (Barcelona Energy Agency, 2006). Other Spanish municipalities followed Barcelona’s lead including Madrid which enacted a similar regulation in 2004. Madrid estimated their results at 28,197 m2 of solar thermal installation by December 2006 equivalent to 19,700 MWh per year and a reduction of 6,900 tons of CO2 equivalent emissions (Institute for Energy Diversification and Savings, 2006).
With the significant results seen in Barcelona and other jurisdictions across Spain, the Spanish Government enacted similar national building codes with the approval of the Technical Buildings Code (CTE, Codigo Tecnico de la Edificacion) in 2006. The building code was an extensive change which included a building energy performance standard that mandated 30-70% of the Domestic Hot Water (DHW) demand be provided by solar thermal energy. The building code applied to any kind of new buildings and those undergoing major renovation. The building code allows for exceptions for DHW that is produced by other renewable sources such as cogeneration. There are exceptions for buildings with insufficient access to the sun or certain historic-artistic concerns. In these cases, the reduced solar contribution by other renewable or efficiency measures leading to similar results (European Solar Thermal Industry Federation, 2007). It is important to note that municipal regulations such as Barcelona and Madrid were allowed to remain in place as long as they were stronger than the national building code. The recession in Spain impacted new building projects in 2008 and 2009 but estimates show that about 80% of the new installations were motivated by the new building codes (European Solar Thermal Industry Federation, 2013).
The Spanish building code provides a great set of lessons and a foundation upon which US municipalities, states, or the federal government could build an effective local policy. The results are clearly evident in Spain. With Spain leading the policy innovation, we can and should study and implement similar policies. Hawaii appears to the first US state to follow the Spanish model with a mandate for solar hot water on all new residential construction. This model could certainly be applied more broadly to all new construction in Alabama but the capstone focus will remain limited to new subsidized and HUD housing to benefit Alabama’s poor.
References:
Barcelona Energy Agency. The Barcelona Solar Thermal Ordinance: A local contribution to global sustainability. www.barcelonaenergia.com July 2006.
European Solar Thermal Industry Federation. Solar Ordnances. www.estif.org 2013.
European Solar Thermal Industry Federation. Best practice regulations for solar thermal. www.estif.org August 2007.
Institute for Energy Diversification and Savings. The bylaw for Solar Thermal use by the Madrid Town Council: Implementation and Results. www.idae.es December 2006.
SolarBC. Regulations and Government Policies: Building regulations that incorporate obligations for solar hot water are the single most powerful tool for promoting increased use of renewable energy in our homes. www.solarbc.ca 2013.
On my trip, I took the train from Cadiz to Madrid. I could see solar hot water on the homes in the country side. In Madrid, I did not see the solar hot water systems but spent my time at street level looking up at the buildings.
I did not come across any life cycle costs for Spain. From other references, the systems last around 20 years depending on the weather, materials used, water hardness, and maintenance. Some systems build up scale inside the tubes due to boiling on hot days that reduces efficiency. As the scale builds up, flow drops down and more boiling could occur in low flow regions resulting in an increased scale rate.
Israel looked interesting. The return on investment is high in Israel (4 year payoff period) and the desire to reduce oil dependence is also a strong driver. Most folks there view solar hot water as no brainer and install the system regardless of the regulation. That is making the regulation just a formality that needs little to no oversight.
Fascinating information, sailor! I visited Barcelona in 2009, but had no idea about this policy. It’s interesting to me that in a place so rich with historical architecture and charm they’re able to move forward like this, way ahead of the United States. Did you come across any information about the cost savings associated over the lifetime of the solar hot water heaters or perhaps that isn’t available yet since the mandate is so young. I definitely have to check out Israel since they’ve been doing this since 1980 – incredible.