The Régie Communale de Montdidier - Energy mix for the city in the heart of the agricultural plain

Chaire Paysage et énergie (ENSP), 2022

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Montdidier, a town on a rocky outcrop in the heart of the Santerre agricultural plateau

1 - The Santerre plateau, a territory of large-scale agricultural production

The Santerre plateau covers the south-eastern part of the Somme department, one of the largest agricultural production departments in France. It is a silty plateau landscape incised by a few valleys, with large horizons at a more or less constant altitude. The land is rich in agricultural activity, and numerous land consolidations, in addition to the wars, have generated very open horizons, punctuated by a few wooded areas on the less fertile clay soils. The main crops are wheat and sugar beet. The valleys are visible with their riparian vegetation and are sometimes occupied by mixed farming.

2 - Village and industrial buildings

The area is not very urbanised, with a regular network of villages with a few hundred inhabitants and a few larger towns. The traditional cob buildings were replaced by brick after the destruction of the First World War. Agri-industrial landscapes emerged from the 1920s onwards, for the processing of agricultural products (grateries, sugar factories, etc). Grove villages remain (villages surrounded by groves of trees), despite the disappearance of courtyard belts (small gardens adjoining farmers’ houses) and the consolidation of farms.

3 - Infrastructure linked to agricultural production

The cultivated land as far as the eye can see is raised by major roads that run through it. The landscape is marked by vertical elements such as silos, evidence of large-scale agricultural activity and, in recent years, by energy production with numerous wind farms. The silty soils are rich but lack lime, so there are many local quarries to amend the agricultural plots.

4 - Montdidier as a promontory on the plain

Around the town of Montdidier, the plateau is slightly hilly. The town is located on a rocky outcrop, at the crossroads of several major roads, overlooking the Santerre plain. Old working-class neighbourhoods can be found in the lower part and on the outskirts of the town.

5 - Challenges for an area of intensive agriculture in the heart of a wind corridor

Successive agricultural consolidation has led to the abandonment of old buildings. Some villages are deserted. Demographics are in general decline and the population is ageing.

The plateau character and the presence of wind corridors are very favourable for the installation of wind turbines. The exponential development of wind power since 2005 has resulted in a large concentration of wind farms in the area. There are now very few horizons left without wind turbines.

It is in this context, with strong territorial stakes of agricultural production and wind development, that the various projects led by the Montdidier municipal authority are situated.

The Montdidier Municipal Board, a historical local energy player

1 - The local authority, a long history

The Montdidier municipal utility was created in 1925. At that time, electricity was developing in France, but there were still few means of transporting it. Many towns set up a Régie communale to provide electricity. These were public establishments belonging to the town hall. Initially, the role of the Montdidier Régie was to distribute and supply electricity to the whole town. After the Second World War, many electricity networks were destroyed. EDF was created in 1946 to produce, distribute and supply electricity throughout France. This led to the disappearance of many local authorities. The town of Montdidier decided to keep its Régie. Its agents became employees under private law within a public structure. Until the 1990s, the Régie retained its sole role as distributor and supplier. The first turning point came in 1991, when EDF asked the Montdidier Régie to acquire a 10 MW oil-fired power station. It served as a relay in the event of a power cut on the national grid or during peaks in consumption. The company thus became an electricity producer. The second turning point came in the 2000s, when electricity supply was opened up to competition. The utility then decided to diversify, with the production of renewable energy. This production was carried out without private investment, and all the revenue generated by the implementation of renewable energies (RE) was reinvested for the municipality.

2 - Wind energy in the Somme and the contribution to the municipality

In 2003, the local authority launched its first renewable energy project, in the form of a wind farm. This project was based on the regional wind energy plan drawn up by the Picardie region (now Hauts-de-France). The company is taking advantage of an energy resource that is very present in the region (remarkable wind corridors), while taking into account regional recommendations, particularly in terms of landscape. This determines the choice of location and a certain type of machine adapted in terms of size. The wind farm was inaugurated in 2010, becoming the first French public wind farm. Its aim is to produce directly for Montdidier. The wind turbines currently supply half of the town’s energy demand. There is no private investment, part of the financial contribution generated is paid directly to the municipality. This results in municipal aid for energy management for the inhabitants of Montdidier, for example for people who want to improve the thermal insulation of their homes.

3 - The energy mix and the daily presence of renewable energy in the heart of Montdidier’s landscape

In 2004, a framework agreement between the town, the Hauts-de-France Region, the Ademe and the local authority provided for a « pilot town in energy management » operation. This led to the creation of an energy information centre in 2006, as well as the launch of a CEIR (rural intercommunal energy council) and an OPAH (programmed housing improvement operation).

In 2008, a communal heating network was created. The authority uses the hospital’s existing gas boiler and has a biomass boiler built. The two boilers supply the municipality’s major consumers: the hospital, the high school, the college and a school.

Since 2009, a dozen photovoltaic projects on public and private buildings have been launched, with installation assistance provided by the Régie for private buildings. Thermal rehabilitation work is also carried out.

In 2011, a ground-based photovoltaic plant was created near the utility.

In 2009, the Montdidier lighting authority replaced 300 mercury lamps with sodium lamps. These consume less electricity and save energy. This new technology also makes it possible to make the most of the power reducers already in place and thus to make further savings on electricity consumption.

Since 2020, a new biomass boiler and a new gas boiler are being built to extend the heating network.

This energy mix and this global vision of the production, distribution and supply of electricity in a short circuit, as well as actions to raise awareness and help individuals, allow the Régie to propose a coherent and evolving plan for Montdidier and its energy consumption. The town is dotted with signs of the presence of renewable energy, and the notions of renewable energy and sobriety are integrated into daily life.

The energy mix, multiple production methods for local and shared consumption

Montdidier’s local authority currently has 13 employees. They come from a variety of professional backgrounds and are thus able to manage the many projects carried out by the authority as they develop

1 - Wind turbines on the agricultural plain

4 wind turbines of 2 MW each and 80 m high have been installed to the south of the town since 2010, on private agricultural land, part of the municipal territory. The 8 MW installed produce a total of 17 GWh/year, i.e. half of the town’s electricity consumption. However, it is not correct to speak of autonomy for half of the city, as there is no electricity storage for the moment. The production is redistributed to the EDF network when local consumption drops. The four communal wind turbines can be seen in the background of Montdidier, to the south from the heights of the town, and from the plateau to the north of the town. They are part of the daily landscape, which is also full of wind turbines on the whole of the Santerre plateau.

2 - Solar energy on roofs and on the ground, elements that are part of the city’s landscape

The Régie is installing various photovoltaic systems, including a 2,000 m² photovoltaic park on the ground at the entrance to the Régie’s buildings. It is visible from the road and offers a showcase effect. Photovoltaic panels are installed on the roofs of certain municipal buildings (schools, biomass boiler, etc.), combined with thermal renovation of the buildings.

3 - Educational and communication tools for energy management by all

Municipal tools have been put in place to distribute aid to residents. Many individuals ask for help to install photovoltaic panels on their roofs. The Régie is present to help with the purchase and installation. A current extension of the heating network is presented to the inhabitants in the form of flyers and surveys distributed. New networks are buried under the pavement. It is perhaps regrettable that these works do not give rise at the same time to new, more qualitative developments for the public space.

4 - Dual energy: diversity and adaptability

The Régie has set up its heating network with a biomass heating plant (85% of production) and gas (16%). The hospital’s gas boiler room has been made available and a biomass plant has been built. A new plant is under construction, which will combine a gas and biomass heating plant in the same building. It is being built right next to the first biomass plant to facilitate the routing of the production. Six kilometres of underground networks are added. This new boiler is placed on the heights of the Montidider hill, along the road to facilitate the transport of materials. It is visible from the plain to the north of the town. Its two large red chimneys are a signal. It emerges from the trees, a way of evoking its function as a wood boiler. The wood used for the biomass boiler is mainly supplied by the ONF, notably from the forests of Compiègne and Créas, as well as from some farmers on the Picardy coast. It must not come from forests located more than 50 km away.

With two types of boiler rooms (biomass + gas), the company has a dual-energy system, which is useful as a precaution in the event of a problem with one of the plants or the network, and is even essential for consumers such as the hospital, which must be constantly supplied with energy.

The Montdidier energy company, a long history of innovative projects

1 - Towards energy autonomy, the question of everyday landscapes

As a continuation of its renewable energy projects and its desire for energy sobriety, the Montdidier energy company wishes to move gradually towards complete control and energy autonomy. To this end, an increase in wind power production is in view in order to increase its production of green energy, to be in surplus and to move towards storage. At the time of the first wind project in Montidier, few wind farms appeared in the vicinity; there were no objections from the inhabitants. The results of the public enquiries carried out on the extension of this park are still favourable, despite the multiplication of projects since then; this probably reflects the awareness of the inhabitants of the benefits of renewable energy, acquired through the municipality’s quest for energy autonomy. The excess electricity produced will be stored using hydrogen. It will then really be possible to talk about autonomy. A heating network project is linked to this electricity project, with a cogenerative heat engine associated with the storage of wind turbine production. The recovery of the heat emitted will enable a new gas-fired heating network. Instead of letting the heat evaporate, new energy is created by using the surplus. Here the company anticipates the potential limitations of wood-fired heating systems. Their use is difficult to control over time, as there is an increasing demand from different municipalities, without necessarily more supply of resource material. It is therefore interesting to plan for the future with new heating networks.

2- Networks of local authorities and the TEPOS network

Montdidier has one of the most involved French utilities in the issue of renewable energy (80 utilities currently in France). As a member of the Positive Energy Territories (TEPOS) network, the Montdidier local authority is a well-known example of a local energy management and renewable energy development policy.

3 - Wind turbines in the Hauts-de-France region: territorial policies to be adapted

The existing wind farm of Montdidier is located in a zone determined as favourable by the wind development plan carried out by the region in 2003; it is however on the edge of a zone of vigilance. Today, the Region is again mapping wind energy development. The landscape data of the former regional plans are taken up again, to which the risks of visual saturation are now added.

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