Going Geothermal

Going Geothermal

Mark Elzinga held nothing back when he built his four-acre organic greenhouse at Elzinga & Hoeksema in Portage, Mich.

He spent money, took risks and entrusted a lot of people with the future of his operation–people like Stephen Hamstra, executive vice president at GMB, who helped design the solar-geothermal energy system that should provide 80 percent of Elzinga’s heating needs. The GMB-designed system should cut down on Elzinga’s energy costs, as well, and significantly reduce the greenhouse’s carbon footprint.

“The geothermal hybrid is a new thing,” Hamstra says. “I’m not aware of a greenhouse that’s done it like this. We presented the concept in 2006 in a white paper at the International Ground Source Heat Pump Association (IGSHPA) annual meeting in Albany, N.Y., and there was a lot of favorable response.” 

One Of A Kind

Elzinga was among the first to take notice, and he now has an impressive solar-geothermal system that includes 200 solar energy collectors, a 60,000-gallon insulated water tank and a heat exchanger that includes 26 miles of polypropylene tubing sunk in 200 wells that are each 300 feet deep.

The system uses Michigan’s year-round ground temperature to create hot water that’s stored in an above-ground tank and available for most of the greenhouse’s heating needs. In the summer, only a handful of heat is obviously needed in the building, yet available heat from the sun and air is abundant. So that excess heat is pumped into the ground and available to Elzinga the following winter.

Another part of the GMB design involves two air-handling units that sit outside the greenhouse.

“They’re basically fans and big radiator coils,” Hamstra says. “Each one moves 100,000 cubic feet of air per minute. If the air temperature (outside) is warmer than the soil temperature (underground) in the earth heat exchanger, we’ll turn on a pump and circulate cool water through those coils and blow warm air across the coils to also try to capture free solar energy and warm the soil.”

As reliable as Elzinga’s geothermal system is, the greenhouse can’t exclusively depend on heat from it year-round. Once cold temperatures arrive, high-efficiency boilers kick in to make up the difference that the heat pump cannot fill. And, if for some reason the geothermal system needs to be turned off, the boilers are capable of handling the heating load for the entire greenhouse. 

Greenhouse Rookies

Surprisingly, Elzinga is the first greenhouse GMB has ever served. The architectural and engineering company based in Holland, Mich., has mainly worked with the healthcare, corporate and education sectors. And, according to Hamstra, few of his peers have even thought much of having greenhouse growers as clients.

“It’s a huge market with a huge need, and the response is typically that the greenhouse market has been characterized by low-cost heating systems and that growers will put in the minimum to get by,” Hamstra says.

Elzinga’s vertical closed-loop system certainly bucks that trend, but the idea behind it is that the long-term benefits will eventually offset the costs upfront. Still, there’s more to geothermal heat systems in greenhouses than growers simply being open to invest in their futures now. Each greenhouse structure is unique, Hamstra says, and any system GMB installs is custom made.

At Elzinga, GMB was called on midway through the building process. But the earlier it could have been involved, the better, Hamstra says, because geothermal applications are functions of the greenhouse site.

If, for instance, GMB was involved with the Elzinga project at the start, it might have been able to put the bore field underneath the greenhouse itself. And that, among other applications, probably could have reduced the amount of area taken up by various parts of the system, too.

“We need some real estate to do this,” Hamstra says. “Talking to one grower who has a huge aquifer available and a big irrigation system with greenhouses and large open fields, a ground-water heat pump system is certainly a possibility. If you’ve got a good source of ground water, a good place to get rid of it after you’ve just pulled some heat out of it and no bacteria that will cause problems over time, it can work well.” 

Thinking Ahead

A geothermal system can also work well for a greenhouse, Hamstra says, if it collaborates with another building, particularly one that’s refrigerated. In a study conducted last year on a Meijer store in Michigan, GMB found that the store rejects nine times more heat each year than it needs.

Following the study, Hamstra did a computer simulation that gave the Meijer store a geothermal heat pump system, and he put the store side-by-side with Elzinga’s greenhouse. He then found that if Meijer’s waste heat was moved to the greenhouse, the size of Elzinga’s geothermal heat exchanger would drop in half in a virtual building simulation. He also concluded that the greenhouse could use that waste heat to significantly reduce the cost of operation while Meijer had a less-expensive way to lose its heat. “If you’ve got greenhouses that are next to some industrial process–plastic injection molding, even power plants–the waste stream from one industry could become the feedstock for the other industry,” Hamstra says.

As good as that scenario sounds, few growers are positioned right next door to buildings that can accommodate that amount of heat. But if growers are considering geothermal heat pumps for their greenhouses, Hamstra recommends that they consult engineers who’ve gone through the rigors of Certified GeoExchange Designer (CGD) training administered by IGSHPA. The investment is simply too much, he says, to rely on some run-of-the-mill heating company that’s conveniently located.

“I’ve heard reports, even in our area of West Michigan, of people who have applied geothermal pumps in greenhouses and the heat exchanger was way undersized,” Hamstra says. “They pulled the soil temperature down very quickly, and partway through the season it ceased to function.” If applied correctly, growers could see financial benefits for years to come. The benefits of such systems on the environment are big, too.

“Reducing our footprint by only moving energy instead of burning a fossil fuel to create heat is a significant one,” Hamstra says. “I think as an industry, growers have been looking for something to relieve them from these huge fuel bills.”

Leave a Reply

9 comments on “Going Geothermal

  1. i am in the business of building geothermal systems currently i have done one small green house system and works quite well my customer is very happy with it but i have mostly done residential i have the potential for much larger projects i would like to go after. there are many large growers in our area so maybe looking at partnering up with someone who has done larger project and expand our business

  2. I am new to greenhouses but I want a geothermal heating/cooling system for 4 greenhouses. Just wondering how much space is really needed only have about a half acre to spare, is it enough?

  3. I have a good thermal greenhouse question I have been pondering about. When constructing my first portable cold frame I only wanted the cold frame to be as tall as it needed to be for the plant heighth. I thought that the extra room would somehow be all the more space for cold air to hang out. Then I thought maybe it would also be a space where the heat collected during the day to be stored.
    So, my question is that is it advantageous to have extra unused room in a greenhouse to store heat captured during the day? The reason I ask is that I really want to make my next greenhouse a walk-in greenhouse but it doesn’t really “have” to be.

    Thanks,

    Jon

  4. I want to know your experience using underground geothermal water for city building.can you help me? if you help me, i am very thankful. And I wish you happy & health in the new year.

  5. i am in the business of building geothermal systems currently i have done one small green house system and works quite well my customer is very happy with it but i have mostly done residential i have the potential for much larger projects i would like to go after. there are many large growers in our area so maybe looking at partnering up with someone who has done larger project and expand our business

  6. I am new to greenhouses but I want a geothermal heating/cooling system for 4 greenhouses. Just wondering how much space is really needed only have about a half acre to spare, is it enough?

  7. I have a good thermal greenhouse question I have been pondering about. When constructing my first portable cold frame I only wanted the cold frame to be as tall as it needed to be for the plant heighth. I thought that the extra room would somehow be all the more space for cold air to hang out. Then I thought maybe it would also be a space where the heat collected during the day to be stored.
    So, my question is that is it advantageous to have extra unused room in a greenhouse to store heat captured during the day? The reason I ask is that I really want to make my next greenhouse a walk-in greenhouse but it doesn’t really “have” to be.

    Thanks,

    Jon

  8. I want to know your experience using underground geothermal water for city building.can you help me? if you help me, i am very thankful. And I wish you happy & health in the new year.

More From Structures & Equipment...
Gaillardia x grandiflora 'Arizona Apricot'

February 25, 2015

National Garden Bureau Designates 2015 As Year Of The Gaillardia

Gaillardia, also known as the blanket flower, is a member of the sunflower family (Asteraceae) and a long-blooming pollinator plant. It is fitting that the National Garden Bureau has specified 2015 as The Year of the Gaillardia.

Read More
IPPS Sharing Plant Production Knowledge Globally Logo

February 25, 2015

International Plant Propagators Western Region Sets Annual Meeting Date

The annual meet for the International Plant Propagators' Society (IPPS) Western Region has been set for this September. It will take place September 23 to 26 in Modesto, Calif., and will include learning sessions, tours to local nurseries, a research poster display and poster presentations, various networking opportunities and an awards banquet to close the event.

Read More
Evolvulus Blue My Mind

February 24, 2015

Blue Ribbon Bloomers For Greenhouse Production

Grow what consumers want! Surveys show that blue is one of the top preferred colors of today’s consumers. Here are twelve top recommended blue-flowering Proven Winners annuals and perennials to suit your spring production cycle.

Read More
Latest Stories
Outfitting Your Greenhouse

February 24, 2015

Save Energy With The Right Greenhouse Glazing

The glazing you choose can make a big difference in your energy bill and the uniformity of your crops.

Read More
Rough Brothers aeroponic greenhouse project

February 24, 2015

Rough Brothers Takes A Hands-On Approach To Several Pro…

Two projects Rough Brothers worked on for Altman plants in Giddings, Texas, and Scissortail Farms in Tulsa County, Okla., show that pre-planning on the grower's part opens the way for a smooth-running expansion project.

Read More
Michigan State University Extension

February 24, 2015

Ethylene From Defective Greenhouse Heaters Damages Crop…

Malfunctioning greenhouse heaters can lead to crop damage from ethylene and carbon monoxide induced illness for workers. Michigan State University's Extension educators Tom Dudek and Randy Beaudry teach you how to recognize the symptoms and check greenhouse heaters to avoid the concern.

Read More
Stuppy Greenhouse Manufacturing's Rainbow Super Structure

February 23, 2015

Stuppy Greenhouse Manufacturing Says Every Customer’s G…

Well-suited greenhouses that function efficiently for customers arise from involving them in the design process from start to finish. Stuppy Greenhouse Manufacturing put this philosophy on a greenhouse design for a wholesale grower looking to expand his annuals operation. The grower's needs were simple, yet daunting: design a greenhouse that delivers the perfect growing environment, but keep maintenance and operating costs low.

Read More
Havest Automation Robot

February 18, 2015

Robots Grab Hold Of Growers’ Material Handling Needs

Harvest Automation’s HV-100 robots automate one of the hardest, most labor-intensive jobs at growing operations – plant spacing. With more technology coming, investing in robots could become even more realistic for growers of all sizes.

Read More

February 1, 2015

4 Lighting Products For Your Operation

These new lighting products have been developed for maximum energy efficiency in greenhouse production. Check out the slideshow to see which products are right for your operation.

Read More
LumiGrow

January 30, 2015

LumiGrow Expands Customer Base In 2014

LumiGrow, Inc. is adding more than 125 new commercial, governmental and research customers to its roster of customers, and beyond the new accounts added this year, many existing customers significantly increased the number of LumiGrow products they use and research customers made LumiGrow a part of their efforts to add to the body of knowledge about spectral science.

Read More
National Greenhouse Manufacturers Association

January 27, 2015

Stricter Energy Codes May Impact Your Ability To Expand

Are you aware stricter energy codes may be on the horizon that will certainly impact your business in a big way? Here's a Q & A from the National Greenhouse Manufacturers Association that helps explain the dangers of the coming energy codes and what we as an industry can do to prevent them.

Read More

January 27, 2015

10 Questions To Ask Before Purchasing A Greenhouse Cove…

Whether you’re replacing an existing greenhouse covering or building a new greenhouse, it’s a significant investment, so you need to make sure you have the right type of covering to suit your needs and budget. What’s more, with production costs on the rise, you can’t afford to have anything less than a durable, high-quality covering that is energy efficient. To make a smart purchase, do your homework before you buy. A good place to start is by answering the following questions, which will help you separate the good products from the mediocre ones.

Read More

January 26, 2015

Warehouse Growing Works With The Right Variables

The debate about whether warehouse growing or greenhouse growing is more efficient and profitable is largely based on grower preference, types of plants grown and available technologies, according to various industry players. Traditionally, greenhouse growing has been the norm. However, warehouse growing is becoming increasingly favorable with certain growers.

Read More

January 26, 2015

Greenhouse Growers Look To Build And Retrofit In 2015

You’re likely to see more construction work going on in the greenhouse industry in 2015, according to Greenhouse Grower’s 2015 State of the Industry survey. Responses show growers have high hopes for the future, which may be one reason why more of them are looking to spruce up their facilities.

Read More
harvest automation featured image

January 13, 2015

Harvest Automation Extends Robot Rental Program

Harvest Automation's robot rental program proved to be such a success for the company that it is being extended through the spring. The program was unveiled last year as a way for customers to get started with HV-100 robots.

Read More

January 9, 2015

Innovations In Irrigation

Need help improving your irrigation? Check out these new products.

Read More

December 31, 2014

Precision Irrigation: How And Why?

New developments and research in precision irrigation address water use issues and help growers make more informed fertilizer decisions.

Read More

December 2, 2014

Hanna Instruments, Inc. Introduces pH Electrode With Bl…

Hanna Instruments recently released HALO, a professional pH probe with Bluetooth Smart (Bluetooth 4.0) technology that transmits measurement data directly to an Apple iPad running the Hanna Lab App.

Read More

November 24, 2014

Biomass Six Years Later: Would Pleasant View Do It Agai…

Pleasant View gardens installed its first biomass boiler six years ago and has added a second one since. Now it’s reaping the benefits of lower heating costs and dollars saved.

Read More

November 18, 2014

7 New Media And Light Products For Greenhouse Productio…

New media and light products cover a broad sweep of growing conditions.

Read More
Griffin Logo

November 14, 2014

Griffin Greenhouse Supplies Announces Keelan Pulliam…

Keelan Pulliam retires from Griffin Greenhouse Supplies after more than 20 years of service to the lawn and garden industry.

Read More