My energy consumption, my electricity bill, my urban lab

In other words, they want a sustainable living environment that supports a wide range of lifestyles and living concepts, where they can be involved in all essential change and adjustment processes. This is especially true when it comes to the place where they grew up, where they have their roots – a place that for them is synonymous with comfort, identity and safety.

Our cities are currently undergoing rapid change, and in recent years, global trends such as shifts in climate or local structures have drastically altered urban design and planning. Germany in particular is making an intensive effort to whip all kinds of energy-inefficient buildings into shape.

But now the focus is increasingly shifting away from the single residential or office building, school or museum and moving toward the energy efficiency and sustainability of the city as a whole. Politicians, researchers, and businesses plus the entire construction and real estate sector are all calling for the creation of sustainable urban districts.

“There’s no shortage of energy-efficiency concepts and approaches, but putting anything into practice on the city level remains very difficult,” explains Dipl.-Ing. Heike Erhorn-Kluttig. She has headed up the Energy Concepts working group at the Fraunhofer Institute for Building Physics IBP for many years.

“It’s virtually impossible to realize blanket municipal strategies or sustainable development concepts for entire cities in one fell swoop. Instead, you have to be selective and start at the neighborhood level. Since there are no standard solutions, we have to develop economically viable implementation strategies on a case-by-case basis.”

In transforming a neighborhood into a life-enhancing and sustainable place to live and work, it is important to recognize what its strengths and unique qualities are, and then dovetail these elements with development opportunities and embed them in the overall city structure. Decision makers also have to consider how the various systems – building, block, neighborhood, city and region – influence and depend on each other.

Germany’s Federal Ministry for Economic Affairs and Energy (BMWi) aims to achieve an 80 percent reduction in the country’s energy consumption by the year 2050 and plans to double energy productivity (GDP/primary energy consumption) by 2020. In pursuit of this goal, the BMWi is funding the EnEff:Stadt initiative for energy efficient cities.

For years, Fraunhofer IBP’s Heat Technology department has served as a point of contact for ministries, municipalities, energy providers, housing associations and investors seeking a competent partner to explore and test potential ways to economize on energy consumption. The department’s energy experts research innovative technologies and integrated concepts that – implemented under the right economic conditions –maximize energy savings at the neighborhood level. The focus is on transferrable solutions that send a clear message.

Erhorn-Kluttig and her team have been involved in the EnEff:Stadt initiative for the past seven years, researching strategies and working up recommendations for how urban areas can become more energy efficient. This involves drawing on experiences from numerous national and international initiatives and representative practical projects. Defining KPIs and evaluation criteria that highlight economic and ecological priorities is just as big a part of Erhorn-Kluttig’s research as continuously refining planning assistance for community decision-makers and investors.

Neighborhoods are the bridge between individual buildings and the overall city system. To highlight specific development opportunities for planning energy-efficient neighborhoods, researchers classify neighborhoods according to several criteria. These include the type of development, how the buildings are arranged, roadway infrastructure as well as the number, size and uses of residential and non-residential buildings.

As part of her work on EnEff:Stadt, Erhorn Kluttig was lead author of a book on neighborhood energy planning (Energetische Quartiersplanung). The book examines the existing foundation for community-based energy supply concepts, available building-related technologies and various ways to supply energy. It also provides practical information that aids planners in their day-to-day work; for instance, what the current legal requirements are, how the various settlement types are classified, or which planning tools are available.

It might make sense, for example, to take separate, location-specific measures and combine them to achieve more savings through decreased costs; say, connecting a neighborhood to a local heating supply instead of each building having its own boiler. Planners should also remember that individual efficiency measures can interact in multiple ways, for example when renovating a passive house in an area with a district heating supply. 

It’s often a question of reconciling the different priorities and goals of a throng of decision-makers in order to leave no savings opportunity untapped. “If we are to realize the ambitious goals set by politicians, businesses and the public at large then everyone has to work together. This applies as much to urban planners as to local politicians, who have an important say in development concepts and tend to pursue divergent approaches. In conducting urban research, keeping all stakeholders happy while also taking into account ways to increase energy efficiency is a fine art,” says Erhorn-Kluttig.

Renovating long-established city neighborhoods is a challenge that is about more than just the buildings – it’s also about the people who live and work in them. “In the midst of all these plans, we can’t afford to lose sight of the human factor. I believe it’s essential to involve these people in the projects I work on,” says Erhorn-Kluttig. “Innovation also usually has a far-reaching impact on the way people live. I want to reassure them and win them over – and maybe even inspire one or two in the process. This is a fundamental part of my work.”

All EnEff:Stadt participants have made it their mission to meet as many requirements as possible. So what is so special about this initiative? “We use what we’ve learned from completed projects to flesh out evaluation criteria and planning assistance – not just for communities, but also for other players such as public utilities and housing associations,” explains Erhorn-Kluttig. “That’s why it’s important to start where the transfer of know-how actually takes place – so we can share experiences. We’ve set up research teams for every project and the project managers meet twice a year to discuss ideas. Another major feature of EnEff:Stadt is that we make our knowledge available and keep the public up to date about our findings.”

Research projects are currently underway in some urban areas to test different ways of achieving savings and integrating renewables. Planning assistance plays a role here, making it easier to draw up community-level concepts. Other key elements of the research projects include software tools for designing and implementing innovative technologies, new measuring techniques, energy management and quality assurance systems, and models for energy and carbon footprints.

For the initial planning phase, Fraunhofer IBP developed a software package that helps urban planners, environmental officers, investors and housing associations involved in construction or renovation projects to design energy-efficient neighborhoods. The District Energy Concept Advisor software makes it possible to forecast early on how energy-efficient a given project is likely to be, furnishing planners and investors with essential information before they get into the complexities of detailed project planning. More information about the tool’s special features can be found in the software brochure (German).

“My working group and I get to actively help shape Germany’s transition to a new energy economy – that’s very exciting,” says Erhorn-Kluttig. “Neighborhoods offer much more room to maneuver compared to single buildings, but are also far more complex systems. Communities therefore have to be more active and forward-looking when it comes to urban planning and neighborhood development. The next milestone for our research work will be to take the success we’ve had in harnessing the vast potential for conserving energy, improving efficiency and using renewables on a neighborhood level, and transfer this to entire cities.”