A very green greenhouse projectCalifornia’s Houweling’s

Hothouse Group

is taking sustainable

farming to a whole

new level with its

new greenhouse

project, which

incorporates both

solar PV and a

solar thermal array.

By Diane Mettler

Not many people can use “high tech” and “tomato farm-ing” in the same sentence, but Casey Houweling certainly can. Houweling’s new 20-acre green-houses in Camarillo, California, are raising the “sustainable” bar when it comes to growing tomatoes—and alternative energy. Houweling, president and CEO of Houweling’s Hothouse Group, has spent years planning, permitting, and building what is arguably the most sustainable greenhouse operation in the world. In fact, it’s the world’s first high-volume greenhouse to bring to-gether hybrid energy sources, nutri-ent and water recycling, and conser-vation systems. Construction on the project be-gan in July 2008, and the greenhous-es were completed in September

and November of 2008, with the solar array being energized late in June of this year. This past May, more than 500 people from around the world came to see the results. There was a lot of excitement about this first-of-its-kind complex, with a $50 million price tag, that was using technology to take advantage of every kilowatt and ounce of water available. The operation includes, among other things, two 20-acre Ultra- Clima greenhouses, a five-acre wa-ter retention pond, five acres of solar panels installed over the water reten-tion pond, and a solar thermal array designed into the roof of the new packinghouse. The two Ultra-Clima greenhouses were designed by KUBO Greenhouse Projects. They allow Houweling to reg-

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ulate air humidity and temperature and achieve high production yields through increased light levels and enhanced carbon dioxide levels. By eliminating 90 percent of the roof vents, Houweling was able to in-crease light levels in the greenhouses by 16 percent and reduce the loss of carbon dioxide he injects through the air circulation system. The greenhouse water treatment system recycles condensation, rain, runoff water, and fertilizing nutrients. This has resulted in a 66 percent de-crease in water use and a 50 percent decrease in fertilizer use. New computer technology lets Houweling track all this informa-tion in real-time, giving him unprec-edented control of the growth of his tomatoes.

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A very green greenhouse project

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The project included approximately 500 solar modules on the roof of the Houweling’s Hothouse packinghouse. Since the packing-house building was new, they worked with the structural engineer who did the design to integrate the solar mounting system right into the roof structure—and they saved money.

Houweling installed the solar PVtocutdownonelectricitycosts.Al-though the solar array hasn’t beenrunning long enough to produceexact figures, Houweling estimates it will cover approximately 50 percent of his electrical needs—and elimi-nate over 1.5 million pounds of C02 emissions annually. The 1 megawatt solar thermal array isusedtoheat thewater thatcontrols the nighttime temperature of the greenhouses. Heat collectedfrom the panels, as well as from the warehouse refrigeration exhaust, is stored in million–gallon hot water storage tanks and then circulatedthroughthehouses. Houweling chose American Capital Energy to design and install the solar systems. He says it’s been a good fit. “At the end of the day, you choose a partner that you feelcomfortable with. And that is what thisonewasabout.” The solar portion was a turn-key project, which was something Houweling says he really wanted.“We were putting two other green-

houses into operation, a packag-ing shed, new offices, and other stuff,” he says. “We basically had our hands full, because we were gen-eral contractors for the rest of theoperations.”

Steve Ellicott, director of business development for American Capital Energy, says the first big challenge was finding a place to put the panels. “The unique part about Casey’s application was a water retentionpond. I worked with my design engi-neers and told them this is a perfect place to put a solar farm.” Mountingthesolarpanelsabovetheretentionpondofferstheneces-sary square feet and is a good dual-

purpose use of valuable land; it re-duces evaporation from the pond; and makes a big statement in front ofHouweling’sgreenhouses. American Capital Energy de-signed an elevated structure of

galvanized steel to house the ap-proximately 6,500 Schüco solar panels. The design also included atracking system. “The solar panels will track the sun from sunup to sundown. Basi-cally they pivot on an axis from east to west,” says Ellicott. “By doing that, we get approximately 25 percent more energy out of the solar panels thaniftheywerestationary.

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from page 13

“We’re seeing more and more companies do this,” says American Capital Energy’s Steve Ellicott. “They’re thinking about the double green effect—making money, lowering their operating costs, and being proud that they’re doing something positive

for the environment.”

QuickMountPV-EnergyAd.indd 1 10/1/2009 11:49:43 AM

So there’s a big economic gainby doing that, in terms of quickerpayback and greater long termsavings.” For the packinghouse, a moretraditional solar thermal system wasdesigned—approximately 500 solarmodulesontheroof. “Because it was new construc-tion,wewereabletoworkwith thestructural engineer who designedthe packinghouse, to integrate thesolar mounting system right into theroofstructureandsavemoney,”saysEllicott. Thedesigns,inparticularthereten-tionpondstructure,mayhavebeengenius,buttheywerenewconceptsto Ventura County and gave thempause. Toputthepermittingproblemsinperspective,Ellicottsaysnormalper-mittingtakesanywherebetween30to 60 days. Houweling’s permittingtooksixmonths. “I think the issue was that thecounty has never dealt with any-thing like this before,” says Houwel-ing.“Everythingwasnewtotheguys,andtheydidn’tknowhowtocodeit.Andtheydidn’tknowtheengineer-ingthatwasneeded.Itwasbreakingnewgroundforthem.” But aside from the permitting is-sues,Ellicottsaysitwasagreatteameffort. “We used a lot of Casey’scontractors that were already fa-miliarwiththeproperty.Sotheguysthatbuilt thegreenhousehelpeduserect the solar system. The electri-cianshelpeduswirethesolarsystem.Theguysthatdidthefoundationsforthegreenhousesandpackinghousedid the foundations for the solarsystems.” Houweling’ssystemiscurrentlynetmetered—basically the meter spinsbackward when the system is pro-ducing more solar energy than thenursery is consuming. The businessthengetsretailcreditforthekilowatthoursputbackintothegrid. Thesystemisalsomonitored24/7byathirdparty.Thedataisavailabletoall involvedwiththesolarsystem,includingHouweling’scustomers. “Italsohelpsusasamaintenancetool,”says Ellicott. “If something shouldhappen,wewouldgetanalarmthattellsus that the system isn’tproduc-ingwhatitshouldbe,andwe’dsend

somebody out to fix the problem.” Houweling’s objectives for thehybrid solar system were to help fix his energy costs—in particular natu-ral gas, which has taken enormousswingsoverthepasttwoyears. “Ifyou’reinanoperationandarepretty reliant on energy costs, andyouhave thosekindof swings,howdoyoueverbudget?”saysHouwel-ing. “How do you put a project to-gether where you’re running it ona 10-year payback plan? How canyoumakeforecastsonwhat’sgoingtohappenwithenergy?” For those reasons he wanted tocreate as sustainable an operationas possible, but also one where hecould maintain his operating costs.“Basically we wanted to fix our oper-atingcostsforthelongerterm.” Although Houweling was initiallylookingata10-yearpaybackforthe

entireproject,he’snotcarvingthatinstone.“Itreallydependsonproduceprices,”hesays.“ItalsodependsonthevalueoftheU.S.dollar.” Astheprojectcomestocomple-tion, Houweling says it’s turned outvery well. “Aesthetically, it looksgreat.AndI’dliketoexpandtheso-larinthefuture.Rightnow,therearelimitsastowhatwecandoasfarastheregulationsareconcerned.” For Ellicott, the highlight of theproject was being a part of abroadersolutionthatHouwelinghasdeveloped. “We’re seeing more and morecompanies do this,” says Ellicott.“They aren’t doing these things be-causetheyaretotallygreen.They’rethinking more about the doublegreen effect—making money, low-ering their operating costs, and be-ing proud that they’re doing some-thing positive for the environment.Caseyhas taken it toanother level,

which makes all of us at AmericanCapital Energy proud to be associ-atedandtobeacontributortosucha worthwhile and forward thinkingendeavor.” For Ellicott, though, there arebigger, more personal reasons. “Ascornyasitsounds,it’skindofapatri-oticbusiness.WeinAmericahavetoget the energy problem figured out if wewanttocontinuetohaveanin-fluence on how the world operates in the future. And if we don’t, thenwe’re going to play second fiddle to whoeverdoesgetitright,”hesays. “Inmyopinion,alternativeenergyproductionisanunprecedentedop-portunity for America to embrace,”he adds. “We need to figure out the energysolutions thatwillallowus totakeourcountrytonewheights.Ifwedon’t,we’regoingtomissthelargesteconomic opportunity for possibly

thenextfewhundredyears.” Houweling,however, isn’t lookingquitethatfarahead. “The next big challenge in frontofus ishowwecanmaximizewhatwe’re doing,” he says. “The moreequipmentyouputin,themoredialsyouhave.Sonowwehavetolearntooperatewithallthisnewhigh-techequipment and maximize the pro-ductivityofthegreenhouses.” “To build it is the easy part,” headds.“Tooperateitiswheretherub-berreallyhitstheroadattheendoftheday. Ithinkwe’redoingagoodjobat it. I thinkthewholecompanyislookingforwardtoseeingwhatwecandowithit.”

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from page 14

The objective for the hybrid solar system atHouweling’s Hothouse was to help fix theoperation’s energy costs—in particular withnatural gas, which has taken enormous price swings over the past two years.

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