Thanks for following the second part of the ground coupled heat pump design. If you haven’t already, now’s a good time to go back and read Part 1. In the first part of this post, we discussed the importance of understanding thermal imbalance in a ground source heat pump system and the longevity impacts associated with an imbalanced system. Despite the issues associated with a thermally imbalanced system, there are ways to address building loads with additional technology that will further enhance the performance of the ground-coupled heat pump system, as well as provide long term performance.
The ground source heat pump is a wonderful technology that will be vital in achieving energy efficiency goals this century. This technology isn’t new, but it is beginning to become more accepted as a viable solution for large scale, high efficiency HVAC performance. There are two main types of ground source heat pump systems: those that are “Ground Water” (also called Open Loop) and those that are “Ground-Coupled” (also called Closed Loop), see Figure 1 below. In either case, the water from the ground is pumped to a heat pump, where heat is either extracted out of or rejected into the ground and moved into or out of the conditioned space.
As the newest engineer to join the Cx Associates team, I have had the immense pleasure to be able to approach buildings from a different angle than in my previous work experience. In my former work as a mechanical design engineer, the focus was on current building technologies and keeping up with the most cutting-edge designs for our systems and buildings. Don’t get me wrong, looking to the future of efficient building technologies is tremendously important, but as someone who is concerned about the current state of the environment and ensuring there’s a habitable world for generations of living things to come, I found it hard to believe that new buildings alone are capable of being more than a small drop in a big bucket. After all, there are only a small number of new buildings built each year compared to the vast existing building stock. A quick look at the numbers from the Commercial Buildings Energy Consumption Survey (CBECS) by the US Energy Information Administration (EIA) will tell you that of the total data set, only about 18% of commercial buildings were built in the most recent 12 years surveyed. (https://www.eia.gov/consumption/commercial/data/2012/bc/cfm/b8.php)
The best time is now to replace an old R-22 refrigerant system with an environmentally-friendly alternative.
For better or for worse, we no longer live in the days of hairspray. Our ’do’s style may have suffered slightly, but our environment has benefited greatly. When the Montreal Protocol was signed by the United States in 1987, it set a goal of reducing emissions of ozone depleting chemicals, and it has experienced some success…I hope you all celebrated World Ozone Day this month on September 16th! Many people may be blissfully ignorant of the changes to their aerosol products in the last 30 years thanks to the Montreal Protocol, but in the HVAC/R industry, we’re continually aware.