Ground Heat Exchanger (GHE) is the key to the efficiency of a Ground Source Heat Pump (GSHP). However, GHE is not standardized as other parts of the GSHP. It is basically a bunch of tubes that need to be properly sized and burred in the ground. Improperly sized GHE can lead to chocked flow and higher pumping cost or stagnate flow and less heat transfer.

Sizing-Ground-Heat-Exchanger

Sizing methods and data of GHE are mostly scattered in installation manuals and other documentations, such as the International Ground Source Heat Pump Association Installation Guide and other literature. 

I have listed some general steps and references needed to size a Ground Heat Exchanger. I am also considering to build a webpage to facilitate the calculation.  Do you think if such a utility is useful? Do you know if there is already web based software to do this?  What do you wish such a sizing utility to do?  Please commentate here or at my website http://heatexch.com/2013/09/14/sizing-a-ground-heat-exchanger-for-i....

Views: 1180

Reply to This

Replies to This Discussion

Since the ground loop is the biggest cost of having Geo installed it's critical to get this right for quickest payback time vs. a conventional HVAC system. Too small of a loop and you won't get the rated EER from the unit, too big and you overpay for installation costs. Reducing the installed cost (therefore payback time) is key to making geothermal a successful technology.

Does your calculator take into account the thermal mass of the ground?

The geo system may be designed for a peak load of 42,000 BTU/hr, but the average load may be closer to 480,000 BTU over a 24hr period (24,000btu/hr). The ground due to it's high thermal mass may only need to produce the average capacity instead of peak.

Does the calculator consider installed cost?

Installed cost varies wildly depending on site conditions and labor costs. Installing a larger loop might make sense at the time of construction since the digging equipment is already on site for construction of the building. There are no landscape considerations to worry about. Same may hold true on a rural farm where land is plentiful and labor costs may cost substantially less. In an urban area where installation costs are high, it might make more sense to size for cooling load and have backup heat strips pick up the rest on those really cold nights.

RSS

Featured Forum Discussions

What causes a temperature plane in a home

Started by Energy Wise Solutions in HVAC. Last reply by Peter Krych on Friday. 4 Replies

Velocity Pressure Testing

Started by Horace Douglas Hunt, Jr. in General Forum. Last reply by Horace Douglas Hunt, Jr. Apr 15. 2 Replies

Videos

  • Add Videos
  • View All

Latest Activity

Efficiency First California posted a blog post

Building a Clean Energy Future, Respect for the People Who Will Build It

You don’t need to spend a great of time deal in the policy world before you hear a conversation…See More
10 hours ago
Profile IconDavid G. Tamutus and Sharon Block joined Home Energy Pros
10 hours ago
Gary Reed added a discussion to the group Job Board
Thumbnail

HOME ENERGY ADVISORS WANTED (NEW YORK STATE: Saratoga & Glens Falls Region)

We are currently seeking experienced HOME ENERGY ADVISEOS to join the Jack Hall Plumbing &…See More
yesterday
Profile IconGary Reed and Kurt Shafer joined Diane Chojnowski's group
Thumbnail

Job Board

This group is for posting jobs related to all aspects of the home performance industry including…See More
yesterday
Ron Sarrick liked Energy Wise Solutions's discussion What causes a temperature plane in a home
yesterday
Kurt Shafer added a discussion to the group Job Board
Thumbnail

Installers for Whole House Fans in Various Cities

Invisco Whole House Fan Company in Temecula CA sells the highest performance fans in history. The…See More
yesterday
Kurt Shafer posted a blog post

First Rooftop Whole House Fan for Homes without Attics

Eichler was one of the most famous Mid Century Modern home builders in the 50s and 60s. His homes…See More
yesterday
Travis Lundberg replied to angela stanzione's discussion Used Weatherization and auditing equipment for sale in the group Energy Auditing Equipment for Sale, Trade or to Purchase
"Do you still happen to have a blower door fan, frame and fabric still for sale?  If so please…"
yesterday

Home Energy Pros

Welcome to Home Energy Pros – the unique digital community by and for those who work in the home energy performance arena.

Home Energy Pros was founded by the developers of Home Energy Saver Pro (supported by the U.S. Department of Energy) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network. Please honor our Guidelines

© 2017   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service