Eco Trainers - converting manure to electricity

By Katherine Ford

Trainers at the main French training base, Chantilly, have gone green and are soon to be the envy of their contemporaries around the world with a ground-breaking manure-disposal project. Faced with piles of manure, the bane of all trainers' lives, Chantilly professionals are working together to launch a pioneering scheme which looks set to solve all their problems and at the same time reap both environmental and financial rewards. The 10-million euro project, which should be operational towards the end of 2009, is at the cutting edge of technology and consists of using a process of methanization to convert the waste into electricity which will then be sold to the EDF (French Electricity Board), and into heat which will be used locally.

With some 2500 Thoroughbreds currently in training in and around the towns of Chantilly, Gouvieux and Lamorlaye, the region is France's leading training center and among the most prestigious sites for preparing racehorses in the world. A further 700 polo ponies and 800 riding horses are stabled in the area to make a grand total of 4,000 equine inhabitants. Slightly less glamorous than the haul of Group 1 victories which the four-legged stars of Chantilly bring home each season is the waste they produce. Each horse creates one ton of manure per month. The muckheaps of Chantilly are overflowing and a solution is urgently needed.

Dual-purpose handler Richard Crépon was one of the first to react to the issue, and in early 2006 he became president of the Lamorlaye Bio-Resources Association. "We started to research ways to deal with our large quantities of manure and initially came up with the idea of converting it into compost, or incineration. Local farmers made a small contribution by spreading shavings-based manure on their land. But none of these systems were perfect and we realized that we needed to take control of the situation ourselves." It was then that the current CUMA (Co-operative for the Utilization of Agricultural Material) was born, again under the presidency of Crépon. All of Chantilly and the surrounding area's hundred or so license holders, as well as the towns' riding school, livery and polo proprietors, have been invited to invest the modest sum of 100 euros to join the co-operative which, as Crépon explains, "needs manure in order for our project to be feasible."

The CUMA'S methanization project offers a mutually-beneficial solution to a relatively new problem. Until recently trainers had been able to rely on the abundance of mushroom producers in Chantilly to dispose of their troublesome "by-product." The farmers had chosen Chantilly for its combination of an unending supply of the horse manure necessary for their fungus to grow, and the geological characteristics of the surrounding area. Chantilly is built on valuable limestone which has been excavated over the centuries, notably to construct the spectacular Grandes Ecuries and Chateau which give such charm to France's Classic racecourse. The quarrying left vast underground caves perfect for mushroom cultivation and thirty years ago the area was home to around 25 mushroom farms. "They used to pay us to take away our manure. Nowadays, the industry has largely moved to Eastern Europe, leaving only 4 mushroom producers in Chantilly. We have trouble to get anyone to empty our manure pits and it costs more and more." In Chantilly it now costs 15 euros per ton for trainers to dispose of their organic waste.

Aside from the purely practical inconvenience of evacuating the tons of waste produced weekly, fellow trainer Tony Clout, making a regretful gesture towards a steaming skip full of manure, comments, "we don't realize it, but we contribute to the greenhouse effect every day with all this manure." Clout is another board member of the French Trainers' Association who is an active player in the CUMA. Like all his trainer colleagues, he is primarily concerned by another form of pollution. "Horse manure is officially considered as a waste product and we are responsible for it until it has been completely destroyed. At the moment we have no control over where it ends up. In the current crazy situation, our manure is transported the length and breadth of France. It is always worrying to see piles of manure left standing in fields across the countryside, as they could easily have originated in our stables. There is a real risk that effluent from the waste will pollute the ground water in these instances and the trainer will be held liable and fined."

The increased environmental awareness on the part of the authorities, aside from making them more likely to take trainers to task for inadequate disposal of their waste, has another more beneficial side for the CUMA. "The timing has been ideal for us," explains Crépon. "We started to think about environmentally-friendly ways to recycle our manure at the same time as the government was creating grants and finance schemes for exactly this type of project." One such policy is that proposed by EDF, who pay a special tariff of 140 euros per megawatt hour (compared to usual rate 60 euros MW/h) for electricity produced by renewable sources. This price operates on the basis of a 15 year contract, which the CUMA has secured. "All this is possible thanks to our contract with EDF," states Clout.

Although the finer details have yet to be settled, the principle behind the Chantilly project is the same as that used in Germany by around 4,000 methanization plants for pig slurry. Nevertheless this will be the first time the technology has been used for horse manure. Bruno Battistini, consultant to the Lamorlaye Bio-Resource Association, explains, "We are setting a European and worldwide precedent. The pig manure operations are common in Germany and function in the same way as sewage processing plants as the slurry is highly-concentrated and in liquid form. However this is the first time anyone has attempted the process with dry matter, although it is similar to that used for household waste." In France there are two such plants, in Calais and Lille, for recycling household waste but there remain a number of unknowns concerning Chantilly's innovative project and the CUMA is still conducting research in conjunction with the INRA (National Institute for Agronomic Research) of Narbonne. "Our primary concern is to verify that our horse manure is compatible with the anaerobic breakdown process. We must also be sure of the levels and composition of the biogases produced, and finally that the equipment will stand the test of time." At the current time, around 18 months before the project is due to leave the starting stalls, Battistini and the trainers are certain that the process will work with straw-based manure and are expecting confirmation from the INRA that shavings will be able to be recycled in the same conditions.

Methanization is an anaerobic fermentation process through which the waste is decomposed by bacteria in an air-free environment. The manure will therefore be collected in giant sealed silos, where it will ferment to give off biogas consisting largely of methane and carbon dioxide. These gases will in turn be used to drive turbines which produce the electricity destined for EDF. "While EDF is our guarantee of income," explains Battistini, "we have a legal obligation towards them according to which, in order to benefit from their favorable rates, we must not waste potential energy." The latent heat generated during the methanization process therefore becomes a secondary resource. In addition to its utility in heating the plant's reactors, which need to be maintained at an operational temperature of 131°F, it will also be sold locally for heating purposes.

A 3 ½ acre site has been chosen for the plant, on land owned by the Institut de France and subsidized by France Galop. Its central location at Mont de Po, between the training centers of Chantilly and Lamorlaye, while being practical for trainers, is of vital logistical importance for the sale of the heat. Within just a few hundred meters of the site are the AFASEC jockeys' school and the Bois Larris Red Cross Hospital, the two major clients whose heating systems are to be supplied by the warmth created by the turbines. Their proximity means that a minimal amount of heat will be lost during transfer.  Another bonus with the location is that there is already a 20,000 volt cable running underground across the site to cater for the hospital, which means that no unsightly pylons will be required.

After the three-to-four-week methanization process has been completed, around 60% of the initial volume will remain as biologically stable residue. "Our profitability is also dependent upon the use we make of this residue," says Battistini. "The heat we sell to the hospital and the AFASEC will be running at 100% of its potential in December and January, however that will be reduced to 10% in the summer months. This seasonal issue will affect our global efficiency and in order to qualify for the subsidies on offer, we need to prove that we utilize at least 75% of the energy produced."  The solution to this final conundrum is to recycle the residue a second time to create fuel briquettes. The latent heat which is surplus to requirements over the summer will be used to dry, and then carbonize, the waste from the digestors at temperatures of up to 752°F. The resulting matter will be compressed into briquettes for use either in households or possibly by the AFASEC or the hospital if their boilers could be converted to use this type of fuel. The CUMA are also keen not to leave the remaining mushroom-growers in the lurch and are working together to determine whether the farms can make use of the residue.

The project is expected to cost in the region of 10 million euros. "We have yet to finalize a finance plan as we are still awaiting the various technical validations from the INRA. When we have these we will be able to make an accurate evaluation of the cost of the plant and then source funding for our operation." However Battistini does not have any concerns on this score. In addition to the EDF contract, a whole range of grants and support dedicated to the development of biomass projects and the recycling of waste are proposed on regional, national and European levels, including Grenelle Environment and Brussels. The scheme is supported by the government ministries of agriculture and environment as well as by Finance Minister Eric Woerth, who is Mayor of the prestigious racing town. Indeed the town of Chantilly itself, thanks to its status as a Pole d'Excellence Rurale (Center of Rural Excellence), is eligible for European money dedicated to this type of project. Another source of income could quite simply be a bank loan. This may be more simple than it first appears, as Battistini confirms, "According to a law which was passed five or six years ago, all the major French high-street banks offer loans called ‘Sofergies' which are dedicated to the financing of this type of equipment. The interest rate is negotiable but the real advantage of the idea is that banks must give priority to innovative projects such as ours which will produce renewable energy." In the future, carbon credits may be recuperated by the CUMA, although there is still work to do on this front as they are currently only available for porcine and bovine schemes. Battistini intends to change this state of affairs. "We are lobbying the CITEPA (Technical Interprofessional Center for the Study of Atmospheric Pollution) to convince them to change this ruling and hope to benefit from carbon credits within a year or two."


Richard Crépon and Tony Clout aim to have written off the cost of the factory within seven or eight years, whereas Battistini offers the slightly more conservative estimate of ten years. Whoever is right on this minor issue, the CUMA seems assured of success on both economic and ecological levels. "Once we have repaid the cost of the plant, the trainers, who are the shareholders in the CUMA, will reap the financial benefits," says Clout. "In the future we should be able to return to a situation in which trainers are paid for the removal of their manure, and not vice versa." While the renewable energy supplied to EDF and local services will make a small impact on country-wide electricity production, the project is also advantageous in cutting down on primary pollution which currently originates from the currently steaming muckheaps of Chantilly. The CUMA will seek to standardize manure storage for all the region's trainers so that all waste is kept in covered pits or containers prior to transportation to the plant's closed fermentors, thereby considerably reducing current methane emissions.

While the project is far from completion, the ensemble of favorable circumstances mean that the members of Chantilly's CUMA can be confident of a cleaner, cheaper future in which they will be in control of the manure their horses produce. Their progress will be followed with interest by trainers around Europe and the world.