Thermal energy storage a great choice for builders seeking LEED certification

April 14, 2015

LEED certification for green building has gained serious momentum as more engineers, architects and developers recognize the advantages of integrating more sustainable processes and solutions into their projects and designs. Recent studies indicate that the advantages of LEED-certified green building go beyond environmentally friendly building performance.

According to the U.S. Green Building Council's analysis of the District of Columbia's 2012 Private Building Benchmarking Disclosure, green commercial buildings saw measurable improvement across several important factors. Commercial buildings with LEED certifications averaged 11 percent lower energy use and 16 percent reduced water usage compared to office buildings operating without LEED certification.

Furthermore, engineers and architects can expect continued support for certified projects in the form of federally funded tax breaks. EcoBuildingPulse pointed out that LEED projects boast impressive bipartisan appeal in Washington, D.C. A survey of lawmakers found that nearly 89 percent of Democrats and nearly 80 percent of Republicans are in favor of LEED projects. More importantly, 74 percent of the voter base feels that LEED-certified commercial buildings can generate cost savings by improving how buildings use water and energy.

The question then for engineers and builders becomes not if certifications can be of benefit but rather which LEED credits a building project should aim for, based on the unique demand performance of each commercial building project and the potential solutions available. One such application right for commercial projects seeking certification is thermal energy storage. The technology offers significant ROI for projects and provides the opportunity to earn LEED credits.

Permanent thermal storage solutions ideal for improving HVAC performance
Thermal energy storage provides engineers and builders with the means of changing the way a facility consumes electricity while delivering significant cost savings. Applications that take advantage of thermal storage are adept at helping buildings to permanently shift electricity demand from peak hours during the middle of the day to off-peak hours after dark.

Commercial buildings can achieve this peak load shift by partnering their HVAC systems with a thermal energy storage medium like ice. Using electricity to operate a smaller chiller to freeze ice during the night allows buildings to take advantage of cheaper, off-peak energy rates while lowering peak demand during the day.

The ice can be melted during the day to greatly reduce the need to run a facility's chiller, saving money by minimizing energy consumption during peak hours. Ice is a fitting thermal energy storage strategy for its high latent heat of energy and is subsequently capable of storing 144 BTU/lb of energy, compared to water which can store about 1BTU/lb. Ice can store energy in less space.

Multiple LEED points available for integrating thermal energy storage
Thermal energy storage solutions are a great choice for engineers, architects and mechanical contractors seeking LEED points in the Energy and Atmosphere section. These points are perfect targets when deploying thermal energy storage because targets for certification are compared against ASHRAE standards, which measure energy cost reductions. This is a metric perfectly suited for comparing to the direct, measurable benefits of thermal energy storage.

For example, thermal energy storage can help projects meet Optimize energy performance Point EAc2, a credit earned by exceeding ASHRAE standards by 50 percent, and earn up to 18 LEED points. Installing this technology can also help a project to earn Demand Response Point EA4, a credit worth another 2 or 3 points, by using thermal energy storage to permanently shift peak load hours to off-peak times. Obtaining these points by implementing thermal energy storage can help gain LEED certification and potential cost savings making thermal energy storage technology a worthy potential investment for commercial building projects.