Green Ener­gy on the Farm

Methane, bio­mass, solar pan­els: there is no short­age of resources on farms for pro­duc­ing ener­gy local­ly. From Picardy to Provence, things are pick­ing up steam.

Con­vert­ing waste, byprod­ucts, or bio­mass into ener­gy to heat build­ings or green­hous­es is not a new idea, but the improved self-suf­fi­cien­cy is still attrac­tive. In the depart­ment of Aisne, the Mas­court farm has cho­sen anaer­o­bic diges­tion, on the ini­tia­tive of Sébastien Mas­court, who is pas­sion­ate­ly com­mit­ted to this project.

“Hav­ing already farmed pigs and about 250ac, in 2004 I start­ed think­ing about how to sus­tain the struc­ture of the farm, which I man­age togeth­er with my sis­ter and broth­er-in-law. I made a bet on ener­gy tran­si­tion and explored all the poten­tial that there was on the farm. For a pig farm, there are not very many solu­tions besides ther­mal ener­gy.”

Cogen­er­a­tion

After gain­ing approval from the local plan­ning author­i­ty, in 2014 Sébastien set up his cogen­er­a­tion-anaer­o­bic diges­tion plant, with a capac­i­ty of 250kW. He made the choice to treat the 12,000t of manure from his pig farm to heat the new green­hous­es that he has built on the farm. Green­hous­es in Picardy? For grow­ing what? Red berries! The young farmer didn’t hes­i­tate: he used about 2.5ac of the land for green­hous­es to pro­duce 44t of berries a year and recruit­ed 15 peo­ple to help with the har­vest between April and Novem­ber.

“By pool­ing our three activ­i­ties relat­ing to pigs, straw­ber­ries, and anaer­o­bic diges­tion, we have cre­at­ed syn­er­gy effects and large-scale ener­gy economies.”

Sébastien Manscourt

The farm shop sales are neg­li­gi­ble, the major­i­ty of the fruit going to a com­mer­cial plat­form in Laon, a near­by town. “I still keep a bit of the direct sale, which allows us to have some con­tact with cus­tomers and explain how we pro­duce the fruit, with prac­ti­cal­ly no treat­ment.”

Job cre­ation

The project is going well; the farm pro­duces straw­ber­ries for local sales out­lets over six months, with sev­en vari­eties in total. They are grown above ground, with no treat­ment besides essen­tial oils to pre­vent dis­eases, and the col­lect­ing bas­kets are weed­ed by hand. It’s not quite organ­ic, but it’s close. Addi­tion­al­ly, Sébastien sowed wild plants, like sain­foin and melilo­tus, around the green­hous­es to attract bees and oth­er pol­li­na­tors to the straw­ber­ry plants.

Over half of the green­hous­es are heat­ed by the anaer­o­bic diges­tion unit and the hot water that it pro­duces. After two years of oper­a­tion, Sébastien cal­cu­lates that it will take anoth­er five years for the equip­ment to pay itself off. In total, four mil­lion euros have been invest­ed over five years and today 22 peo­ple work on the farm.

In Picardy, the Manscourt col­lec­tive farm is putting all its efforts into anaer­o­bic diges­tion through cogen­er­a­tion, from live­stock manure but also from all sources of organ­ic waste avail­able in the area of the farm.

Har­ness­ing the local bio­mass

These two years were need­ed to get good points of ref­er­ence. Sébastien men­tions that he has spent many hours mon­i­tor­ing and reg­u­lat­ing his anaer­o­bic diges­tion plant. In his opin­ion, it’s only a first step. He is con­tem­plat­ing build­ing air-con­di­tioned stor­age facil­i­ties. “At the moment this anaer­o­bic diges­tion unit runs on 60% manure and 40% green waste. But I don’t have enough pow­er to heat all my green­hous­es. Hence the idea of expand­ing the anaer­o­bic diges­tion unit by con­vert­ing unused bio­mass, from local sources of waste.”

He already plans to build a grain store on the farm and he hopes to increase his capac­i­ty by dou­bling the num­ber of his live­stock and to con­vert more manure into fuel. His dream is to triple or quadru­ple the plant’s capac­i­ty and to achieve com­plete ener­gy self-suf­fi­cien­cy. “Today, our three activ­i­ties relat­ing to pigs, straw­ber­ries, and anaer­o­bic diges­tion are inter­de­pen­dent. By pool­ing them, we are cre­at­ing syn­er­gy effects and large-scale ener­gy economies.”

With his pas­sion for pro­duc­ing straw­ber­ries, Sébastien Manscourt breeds the finest vari­eties of the plants him­self.

Mis­cant­hus fuel

Anoth­er ener­gy sec­tor is tak­ing root, and that is mis­cant­hus. One of the lat­est suc­cess­es involves heat­ing the Abbey of Ourscamp in Oise with 30ac of the plant pro­duced local­ly by two farms very close by. The mis­cant­hus sup­ply has been con­tract­ed for 15 years. The farm­ers seed­ed it in 2015 on plots that were far from the farms and dif­fi­cult to access, where grain crops were not very prof­itable.

This out­let allows them to diver­si­fy their activ­i­ty, secure a stream of rev­enue and recov­er the invest­ment in plant­i­ng rhi­zomes. The reli­gious com­mu­ni­ty of Ourscamp has installed its new 400kW mis­cant­hus heat­ing sys­tem, replac­ing the old oil heaters, to heat four build­ings and three hous­es. This saves the abbey €60,000 per year in fuel and avoids 230t of CO2 emis­sions per year. By way of com­par­i­son, those are the same emis­sions as 120 new diesel vehi­cles (183g CO2/mi, 9,630mi/year) pro­duce.

Fur­ther south in Drôme, Jacques Vail­lant is also explor­ing every source of ener­gy self-suf­fi­cien­cy. This for­mer physics teacher has many ideas that he is try­ing to get out into the rur­al world. In Mon­téléger, he has set him­self up on a for­mer farm sur­round­ed by just over 5ac of land. “I have been try­ing to elim­i­nate my car­bon foot­print for 12 years,” he says. All means of doing so are good: insu­lat­ing your home with wood wool, small wind tur­bines, water heater and solar pan­els, not to men­tion plant­i­ng mis­cant­hus to pow­er a plant fur­nace.

ANAEROBIC DIGESTION AND BIOGAS OUTLETS

Anaer­o­bic diges­tion is a nat­ur­al process of decom­po­si­tion of organ­ic mate­r­i­al, lead­ing to the pro­duc­tion of bio­gas, which can put to use in mul­ti­ple ways:

  • just for heat (in a boil­er)
  • elec­tric­i­ty and heat simul­ta­ne­ous­ly (in cogen­er­a­tion)
  • bio­methane, which can be inject­ed into the nat­ur­al gas net­work and used for any tra­di­tion­al use of nat­ur­al gas, includ­ing for fuel use.

Unde­mand­ing crop

“Today I have done away with fos­sil fuel com­plete­ly by insu­lat­ing the walls and using the mis­cant­hus heather. I plant­ed this grass myself at two feet per square meter. It’s worth not­ing that this crop is not inva­sive at all. Instead it’s eco­nom­i­cal, sus­tain­able, and easy to grow.” Giant mis­cant­hus, also known as ele­phant grass (Mis­cant­hus gigan­teus) is ster­ile. And when it is fall, we see pan­i­cles appear that do not con­tain seeds: that means it is not con­sid­ered an inva­sive species.

On Jacques Vaillant’s farm, the mis­cant­hus is grown on just under two and a half acres and is har­vest­ed in March when the stems are well dried out. Yield (dry mat­ter) is 4.8 to 5.7t/ac/year on aver­age. Once ensiled, the har­vest is stored under cov­er, before going straight into the boil­er, sup­plied by an auger.

Jacques Vail­lant regrets not hav­ing found a suit­able boil­er in France. In the end he import­ed it from Aus­tria. “This agri­cul­tur­al boil­er allows us to burn any pri­ma­ry agri­cul­tur­al mate­r­i­al. All we need to do is make a lin­ing, since the acids pro­duced by the com­bus­tion attack the inter­nal sur­faces. The clink­er also has to be elim­i­nat­ed with a grille. Final­ly, the quan­ti­ty of air needs to be care­ful­ly reg­u­lat­ed by an oxy­gen probe placed at the exhaust.”

A step towards self-suf­fi­cien­cy

Always will­ing to share his expe­ri­ence, the retired teacher has set up an asso­ci­a­tion in Drôme in order to pro­mote the ben­e­fit of mis­cant­hus for hous­ing. “I think that with a lit­tle over an acre of mis­cant­hus, any­one could heat their home. And a farmer can also use it to run his dry­ing facil­i­ties and build­ings”, he adds. “We need to move to renew­able ener­gy and for every­one to man­age to lim­it their car­bon emis­sions to less than 2t/year… oth­er­wise our world is head­ed for dis­as­ter!”

MISCANTHUS BIOFUEL

There are mul­ti­ple upsides to dry-har­vest­ed mis­cant­hus:

  • a yield of 25 to 70t/ac
  • the sus­tain­able plant forms a soil mulch when the leaves fall in autumn, which avoids any chem­i­cal or mechan­i­cal weed­ing
  • high calorif­ic out­put (4.4MW/t of dry mate­r­i­al) com­pa­ra­ble to that of wood with a high­er ratio of dry mate­r­i­al
  • 7t/ac of mis­cant­hus pro­duce the equiv­a­lent of more than 2,400l of min­er­al oil