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At home with the energy revolution

Germany’s last coal mine, in the industrial Ruhr region, is closing. But few tears are being shed in the local town of Bottrop, where residents are on a very personal journey to a greener future

“Glück auf!” The traditional miners’ greeting has an unusual ring to it in Bottrop these days, because this December the Prosper-Haniel pit, Germany’s last coal mine, will close – ending more than 200 years of history. There will be a ceremony rather like a state funeral, attended by the German president. When the last shift at the colliery finishes, the days of German coal will be over, once and for all. But Bottrop’s mayor, Bernd Tischler, still says “Glück auf!” as he shakes hands firmly.

He has every reason to be cheerful. The western German city he has presided over since 2009 is considered a shining example of how climate change can be tackled – a mining town in the coal state of North Rhine-Westphalia, of all places. Tischler has been invited to China, Russia and Japan; the mayor of Rotterdam recently visited Bottrop, as did urban planners, politicians and entrepreneurs from the US state of Minnesota. They all want to know how Bottrop is already on target to emit 38% less carbon dioxide (CO2) by 2020 through modernisation – a reduction of 100,000 tonnes – and why the city has a good chance of reaching its self-imposed 50% target for reducing greenhouse gases. On the other hand, Germany as a whole will probably only manage to cut its emissions by 32% from 1990 levels by 2020, as the federal environment minister conceded just a few months ago.

A new era is emerging from the ashes of the old one in the huge climate-change laboratory that is Bottrop. Since 2010, the urban redevelopment company Innovation City Management (ICM) has been providing climate-friendly information to citizens on behalf of the municipality. “We are taking action against climate change from the bottom up, and the foundation for this is guidance,” says ICM’s managing director, Burkhard Drescher. Energy experts offer free advice from an office between the railway station and a shopping centre. Their target group within the pilot area, which is home to 70,000 of Bottrop’s 117,000 residents, are small single-family households, of which there are thousands in the former colliery estates.

A mobile office travels around the city too. People can bring their electricity and heating bills and receive suggestions for modernising their homes and information about subsidies. “Interest was restrained at first but now we have waiting lists,” says Rüdiger Schumann, a spokesman for ICM. Evening talks on topics such as heating systems, solar panels or LED lights are popular, and since last year local experts have been visiting homes to offer first-hand advice.

ICM reported this summer that of the 10,000 or so homeowners in the Bottrop pilot area, more than 3,000 had sought advice, and more than half of these had carried out at least one of the energy-saving modernisation measures. “There is nothing mysterious about what we are doing,” says Drescher. “We’re shaking up the town with every means at our disposal – that’s our recipe for activating the local population.”

On Osterfelderstraße, heading out of the inner city to the south-west, stands a single-family home that looks like many others in the area: red brick with a small back garden and white rendered walls facing the street. It was built in the 1950s by a miner and his wife; they are now in a nursing home and the empty house belongs to their grandson, Jan Lachnicht, who teaches at a vocational school. He and his wife, Nina, a nursery school teacher, want to move in with their two children in 2019 but first they want to modernise the property from the ground up, investing at least €100,000 (£90,000).

They called ICM and spent two hours with an architect from the company, looking around the property. They were told it could be connected to the district heating grid, improving their carbon footprint. These systems, which pipe hot water to thousands of homes from one local plant, are common in Germany, producing nearly a sixth of residential heating, but relatively rare in other European countries such as Britain, where they heat barely 1% of homes. These heat and energy networks would be no cheaper than installing a new gas heating system but it would allow them to remove the chimney, creating space to convert the attic into another room. Because the house can be connected to the district heating grid, no subsidies are available for a new boiler (these would otherwise amount to 14%, up to €890), although subsidies are available for other measures that will shrink the carbon footprint of the house. If the Lachnichts’ applications are successful, they could receive a 25% grant towards the cost of insulating the roof (up to €4,210) from Bottrop city hall, and 10% towards the windows, up to €830.

Klaus Wieczorek, a former firefighter who lives a few kilometres away, also received a 10% subsidy. His two-family property, built in 1978, used to have a large glass wall in the stairwell, a feature that was fashionable in the 1980s. After visits from two energy consultants, he replaced it with double-glazed windows. “The stairwell used to get really cold in winter, and extremely hot in summer,” Wieczorek recalls. Even without the €500-plus subsidy, he would probably have installed the window, “but a few hundred euros are certainly a nice perk.” He cannot yet tell whether it will reduce his heating bills, but it has already been worthwhile: “During this hot summer, the stairwell was at long last bearable.” He is now considering exchanging the old, bulky radiators for new, energy-saving models and replacing more windows.

The funding guidelines for the subsidies are probably unique within Germany, having been jointly developed by the city and ICM. They provide for urban development funds to be paid out to homeowners. “And this is done without much red tape,” explains Schumann. “After their energy consultation, people take their reconstruction plans to the town hall, bringing three estimates for the work or materials, and the subsidy is paid out immediately. A few weeks later, someone goes round and checks that the new windows or the insulation have in fact been installed.”

Since 2014, some 500 homeowners in Bottrop have received almost €1.4m in subsidies – and invested nearly eight times that of their own money. A 2015 report estimated that the overall investment by private and public-sector building owners since 2010 came to €183m, with additional investments of €108m pledged up to 2020. “And we estimate that €110m has been paid out to Bottrop tradesmen, engineering consultants and other companies as a result, or will have been by 2020,” says Drescher. “This shows that taking action against climate change can serve as a catalyst for economic growth.” In the interim report in 2015, scientists calculated that the direct and indirect effects on jobs in Bottrop amounted to an additional 1,200 years of employment.

Change pays off

Thanks to an effective advertising campaign and the simple grant procedure, the annual rate of Bottrop’s energy-related modernisation has been about 3% for the past six years, compared with a German average of just below 1%.  It is the highest rate in the country, according to Drescher. “Three-quarters of all residential buildings in Germany are more than 30 years old, so we cannot wait for new energy-efficient buildings to go up,” he says. “We need to tackle the existing buildings much more rigorously.” He reckons a lesson can be learned from Bottrop: “If the energy revolution were organised ‘from the bottom up’ like this throughout Germany, the climate targets could be reached. We are showing people – including those who don’t have deep pockets – that it pays them to save energy.”

Every fortnight, the mayor and the ICM boss meet officials, heads of department and city hall business development staff, project managers, scientists, and representatives of housing associations, energy providers, craftworkers and tradesmen. Together they go through the list of projects, currently some 300, for restructuring the city; they discuss connecting a street to the district heating grid, providing staff bicycles for municipal workers, or converting a petrol station into a “model fuel station” with photovoltaics, air-source heat pumps and LED lights. Other topics include a DIY store’s promotion on energy-saving products, storage batteries and free apps that allow homeowners to find out about possible subsidies for renovating their building.

Central to all this is a public-private partnership in which the city, a fuel company, an estate agent and a consultancy each hold up to 10% of ICM’s shares. Initiativkreis Ruhr, a regional business alliance of some 70 companies and institutions, including heavyweights such as the Germany energy companies RWE and E.ON, and the country’s largest coal-mining company, RAG, holds 61%. “We are supported by industry but we certainly aren’t a contracting agency,” says Drescher. “The companies’ motivation for joining is that this gives them a chance to test new equipment, procedures and services through practical everyday use by their customers, often monitored by scientists. And of course they don’t want to be onlookers left behind during a structural transformation that is going to happen anyway, one way or another.”

The research is being coordinated by a scientific advisory council headed by the Wuppertal Institute for Climate, Environment and Energy. Johannes Venjakob, a geographer who is in charge of the project there, believes that the “Bottrop laboratory” is different from similar projects because the local council has ventured to carry out urban development with a private service provider. “Many local authorities consult planning agencies,” says Venjakob, “but in Bottrop, ICM’s two dozen employees are responsible for the entire management of the projects. Ongoing consultations take place, and in some cases staff are even exchanged between the city hall and ICM. That is unique.”

This is thanks particularly to the mayor, Tischler, and the ICM boss, Drescher – who is extremely well connected, being a former mayor of nearby Oberhausen and managing director of major real estate and housing companies in the Ruhr area. Tischler studied urban development and wrote his thesis on ecological planning at municipal level. As a member of the Social Democratic party, climate, economy and jobs are all equally close to his heart, he says, admitting that he had long worried about what would happen once the monolithic coal industry no longer dominated the energy sector. The most important thing, he believes, is that “we have succeeded in allaying people’s fears that without coal the lights will go out. We have gone in for something new – that is the Bottrop blueprint.”

Architects’ house calls

To Venjakob at the Wuppertal Institute the key point is making the energy transition comprehensible to people. “It is no longer about abstract issues, such as pulling out of coal or nuclear power, but about how, in very practical terms, a homeowner can run a modern heating system, for example. The energy revolution has arrived in their own cellars; it has become a personal issue,” he says.

Petra Berkenbusch-Aust, a local journalist, understands what this means in concrete terms. Replacing the front door and two windows of her 1914 house was very straightforward, she says. She received a 10% grant towards the €4,500 overall cost. “We had to send the town hall photographs of the completed conversion and provide evidence of the payments we had made, and that was it,” she says. Replacing the old gas central heating system with a combined heat and power (CHP) system four years ago was much more complicated. This was also an ICM project, funded by a range of different subsidies and the manufacturers of the equipment. The Berkenbusch-Austs now produce their own hot water with home-generated electricity, rather than in tankless water heaters on several floors. Although gas consumption has increased slightly with the new system, the electricity bills are much lower. “Overall, we save around €80 a month.” Analysis of 52 systems installed in Bottrop showed that CO2 emissions were down by an average of 35%, rising to 73% where they replaced old coal-fuelled heating.

Operating the equipment is simple, according to Berkenbusch-Aust. What is complicated, however, is the tax paperwork; installing a CHP plant made them electricity producers and therefore liable for value-added tax. Their surplus electricity is fed into the public power grid and generates payments – resulting in regular correspondence with the tax authorities. Berkenbusch-Aust also has to deal with the revenue office, to be reimbursed for the energy tax paid by the gas supplier. The tax authorities were not prepared for the fact that energy production was happening in private homes, she says.

The pilot project in Bottrop is due to end in 2020. ICM’s managers want to try it elsewhere: they have developed schemes for neighbourhoods in 17 cities in North Rhine-Westphalia and elsewhere. However, the Bottrop concept cannot simply be copied across Germany because situations vary so much. In one city, the mayor is all fired up about the idea but his administration is not. In another, the local energy provider has its own plans. A third has no district heating grid. A fourth has very few homeowners but lots of apartment blocks belonging to large building societies.

Ecological impact

Even in Bottrop, it’s not all been a success. Few people have been persuaded to switch to public transport, bicycles or electric cars. Commercial enterprises also hung back, because they did not want to disclose their data, or because they lacked the funds or the staff to refurbish.

Calculating the environmental benefits has its pitfalls, too. In some cases, the data is incomplete, or there may be confusion about how to classify particular types of CO2 reduction. The last coal mine was not included in the calculations, for example. “By closing it in December,” explains Drescher, “we would have met the 50% reduction target by the end of 2018.” On the other hand, the conversion of Bottrop’s wastewater treatment plant – one of the largest in Germany – has been included, as an energy consumer that has turned into an energy producer. The scheme, which began a year into the Bottrop project, now accounts for more than half of the entire drop in CO2 emissions (see box).

If Germany’s electricity mix shifts further towards renewables, this too will improve Bottrop’s CO2 footprint – without any change at local level. And if Bottrop’s famous indoor ski slope, built on a spoil heap, could produce the artificial snow for its 640-metre piste entirely from wind and solar power, should that be chalked up as a success for the project and a contribution towards preventing climate change?

Asked if the figures actually fulfil the promise, Venjakob says: “It’s not crucial whether you end up with 50% less greenhouse gas emissions, or 48% or 44%. The crucial point is that Bottrop is revealing model pathways by which climate-friendly urban restructuring can be organised, by highly motivated people activating the population. It is also clear, though, that a transformation of the system itself – phasing out coal power, for example, or turning to different forms of transport – will be essential if we are going to meet the Paris climate targets.”

In other words: homeowners and car drivers can achieve a lot at local level through new heating systems, insulated ceilings and car sharing, but it is up to policymakers to establish the framework. “Off the cuff, I could write down six points that could put the energy transformation and climate protection on the right track within just a few years,” says Drescher. “But I am based in Bottrop, not in Berlin.”


The city of Bottrop holds a 10% stake in Innovation City Management GmbH (ICM) and has despatched five of its staff to work there, at a cost of some €500,000 a year. In addition, ICM won the contract for neighbourhood management, and 4.5 jobs in the six neighbourhood offices are charged to the Bottrop budget at €385,000 a year.

Showcase projects

These include the Emschergenossenschaft wastewater treatment plant, which handles the household and industrial wastewater from Bottrop, Gladbeck, Essen and Gelsenkirchen. It is the largest municipal consumer of electrical power – all of which it has recently started producing for itself from solar, wind and hydroelectric power, sewage gas and the combustion of energy-rich sewage sludge. This has led to an annual CO2 reduction of up to 70,000 tonnes. 

In May 2018, a photovoltaic plant went into operation on the site of a former Bottrop gravel pit, providing solar power for 250 homes. It saves 377 tonnes of CO2 a year.

The Wuppertal Institute for Climate, Environment and Energy describes the House of the Future, in Bottrop-Batenbrock, as “a totally innovative project, nationally”. The 55-year-old family home belonging to the housing company Vivawest has been elaborately renovated, with high-performance solar panels on the roof and one gable wall, 20cm insulation on the outer wall, and triple-glazed windows. The new balconies are made of aluminium and separated from the building to eliminate “thermal bridging” – the loss of heat through parts of a building that have higher thermal conductivity. In the cellar, the old gas burner has been replaced by a heat pump that uses geothermal energy and draws its electrical power from the solar panels. The letter boxes have been moved to a concrete pillar in front of the entrance, also to eliminate thermal bridging. Inside the flats there are LED lights, energy-efficient household appliances and a modern ventilation system.

The building now produces more energy (some 22,000 kilowatt-hours) than the tenants consume (between 10,000 and 12,000kWh, down from 33,000kWh before the renovation). The surplus is fed into the public power grid. However the project will not serve as a template for others. “The aim was never to replicate it umpteen times,” says Vivawest’s Dirk Büsing. “For us the value added lies in its being operated live with tenants, allowing individual components to be tested together with the manufacturers and in some cases with universities, so as to gain new insights.”

Not everything can be easily reproduced elsewhere. The property’s technology is too complicated to be operated by the tenants, for example. But at least the architecture of the balconies has become a standard feature at Vivawest, and LED lights are also being installed in the halls and basements of other Vivawest homes.

There is also an electric charging station in the garage of the House of the Future, powered by solar panels on the roof. “This could be used to charge a car, a scooter or electric bicycles,” says Büsing. “The solar electricity is free. But so far, none of the tenants are making use of the offer.”