Bringing in experts to check on an energy efficiency retrofit after installation is a key step in ensuring that the project is working to its full potential, according to a blog on sustainable development firm New Ecology.
Quite often, retrofits do not perform how the installer predicts. Poor design, incorrect installation, faulty equipment and incorrect calibration are just some of the variables that can lead to an under-performing retrofit, the blog says. But by having someone who knows the equipment visit and recalibrate or make adjustments to the installation many such under-performance problems can be overcome, the blog says.
The blog uses the example of a 17-unit mid rise Boston apartment building built in 1980 that uses a single gas boiler. In November 2012 the owner replaced the boiler switching from an older atmospheric boiler to a modulating condensing boiler. The boiler was expected to see a 26 percent reduction in gas usage.
After the first winter it became apparent that the boiler was only delivering savings of just 11 percent, after weather adjustment. The following spring the team returned to the building with a representative from the boiler manufacturer and the installer. Over the course of the visit, they adjusted the settings on the boiler based on findings from the visit. Specifically, the team lowered the boiler’s domestic hot water target temperature, limited the boiler’s modulation to ensure longer run-times, and optimized the boiler for domestic hot water. They also lowered the temperature of water in the heating loop to ensure water was not hotter than it needed to be, the blog says.
Since the adjustments were carried out, the boiler’s summer energy use was 20 percent less yer-on-year and the heating usage in September and October was 37 percent and 42 percent lower year-on-year, the blog says.
The energy efficiency retrofit program at the Empire State Building has exceeded guaranteed energy savings for the second year in a row, saving $2.3 million, the team that developed the energy efficiency program said in June.
In 2009, the Empire State Building began a comprehensive retrofit at the property. In 2011, the building beat its year-one energy-efficiency guarantee by 5 percent, saving $2.4 million. In year two, the property surpassed its energy-efficiency guarantee by nearly 4 percent.