HVAC Breaking News / News

Nov. 16, 2011: Report Highlights Benefits of Hybrid Ground-Source Heat Pump Technology

WASHINGTON — The U.S. Department of Energy (DOE) has announced the availability of a report — Hybrid Ground-Source Heat Pump Installations: Experiences, Improvements and Tools — that DOE says demonstrates hybrid ground-source heat pumps (GSHP) as a viable solution to reduce energy use in commercial buildings. The report states that new hybrid systems significantly decrease upfront costs while delivering financial and environmental benefits nearly equivalent to standard ground-source heat pumps. With its lower price, hybrid GSHP technology could be deployed widely, saving energy and money in new and existing commercial, industrial, and institutional buildings, according to the report.

DOE, Alliant Energy, and Madison Gas & Electric co-funded the study, which analyzed operating data from three working hybrid GSHP systems. The Energy Center of Wisconsin, with assistance from the University of Wisconsin Solar Energy Laboratory, observed two hybrid systems in Las Vegas and one in Madison, Wis., for one year to examine hybrid GSHP in climates with different heating and cooling needs. In all three cases the hybrid design was effective in comparison to other HVAC system designs. The study validated hybrid systems as a cost-effective alternative to traditional ground-source heat pump systems.

In standard GSHP systems, also known as geothermal heat pumps, a large underground heat exchanger made from a loop of plastic pipes is buried or drilled into the ground. A fluid circulates through the pipes, to move heat between the in-ground heat exchanger and a heat pump, which regulates building temperature. The upfront installation cost for this underground loop is significant, up to half the cost of the entire system, but necessary to achieve the desired temperature levels.

With the hybrid system, the size of the underground loop is significantly smaller, making drilling less expensive and less invasive. To compensate for the smaller loop system, conventional technology (such as cooling towers or boilers) is used to meet a portion of the peak heating or cooling needs. Balancing the load of the GSHP with traditional HVAC equipment lowers up-front costs, while still providing the energy efficiency of a GSHP. This study showed that due to typical building load fluctuations, the standard equipment runs so infrequently it doesn’t substantially reduce the energy savings.

With DOE support, the Energy Center developed documents and tools for HVAC system designers to use, including free modeling software that can assess the benefits of applying the hybrid GSHP approach on building projects. The software can be used to:

• Determine how much money a building owner can save by choosing a hybrid geothermal system.

• Select optimal sizes for the equipment in a hybrid system.

• Compare different hybrid geothermal installation approaches to understand the financial, energy, and environmental impact for a given building project.

• Analyze the effects of different control strategies for a geothermal or hybrid system, to keep maintenance costs and energy bills as low as possible.

For more information, visit www.ecw.org/project.php?workid=1&resultid=464.

Publication date: 11/14/2011

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

You must login or register in order to post a comment.



Image Galleries

2015 HARDI Fly-In

Highlights from HARDI's Congressional Fly-In in Washington, D.C. Post date: May 28, 2015.


NEWSMakers: Clint Schreck

Clint Schreck, general manager, Columbus Worthington Air, Columbus, Ohio, discusses winning Angie’s List Super Service Award, how to handle online reviews, and much more.

More Podcasts


NEWS 06-01-15 cover

2015 June 1

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe


The EPA has approved several hydrocarbon (HC) refrigerants for HVACR applications. Do you support the use of HCs?
View Results Poll Archive


2015 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research


Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.


Magazine image
Register today for complete access to ACHRNews.com. Get full access to the latest features, Extra Edition, and more.


facebook icontwitter iconyoutube iconLinkedIn i con