Redeveloping an urban district represents not just an architectural challenge - the tenants behind the facades must also be taken into account. Those involved in the "Weingarten 2020" research project are aiming to meet both demands. With the involvement of the Fraunhofer Institute for Solar Energy Systems ISE, they have created the first passive high-rise building in a district of Freiburg. A further important milestone was the optimisation of the energy supplies.  more...

Instead of screwing various module and collector types for solar power and solar heat on the roof, an obvious idea would be to use a hybrid collector that can do both and which creates a uniform appearance. In addition to generating photovoltaic electricity, which only utilises 15-20 % of the incident solar radiation, a so-called PVT collector can use the remaining radiation energy for generating heat. Researchers are working on optimising the output and production of these systems.  more...

The economic and ecological success of many CHP plants, district heating networks and large-scale solar power systems very much depends on the utilisation of heat outside of the heating periods. An increasingly interesting market for low-temperature heat is cooling and air-conditioning buildings as well as generating process cooling energy with thermally driven chillers. Scientists from Berlin and Bavaria have developed a new generation of particularly compact, efficient absorption chillers with small capacities for cooling and heating operations.  more...

Fuel cells have unique abilities: in contrast to other co-generation (CHP) plants, they directly convert the chemically bound energy of fuel sources such as hydrogen or natural gas without using a flame. If they are deployed in heating devices, they generate electricity and heat efficiently. Indeed, they are considerably more efficient than combining conventional electricity generation and condensing boilers.  more...

Large volumes of carbon (coke) are used for the melting process in the cupola furnace, whereby a combustible process gas is formed as a by-product. This so-called cupola furnace gas has a low heating value and has previously been completely combusted for generating the hot blast in the cupola furnace's recuperator. However, in this process only around 35 % of the contained energy is used thermally. Now it is possible to utilise the remaining 65 % of the chemically bound energy that was previously not used in most foundries: a modified biogas combined heat and power plant runs with cupola furnace gas (CFG) from the melting furnace.  more...

In future, electricity grids will have to transport large quantities of electricity from renewable energy sources fed centrally and decentrally. Plus, we need greater reserves, storage facilities and flexibility in the electricity market due to the fluctuating supply. In the "Modellstadt Mannheim" project, a virtual energy marketplace is being developed for energy generators, consumers and grid operators. Customers can see the source and price of their electricity and influence them directly via the timing and extent of their consumption and the delivery from their own generation systems. This approach also includes gas, water and district heating.  more...

There are already more than 100 regions and many rural communities that are promoting sustainable development based on renewable energies. After developing individual concepts and strategies, the lengthy and often very complex implementation begins. A research project organised by the German Federal Ministry for the Environment has been supporting these regions in conceptual and technical terms since 2007. This project is being conducted by the deENet competence network and the University of Kassel, and is being advised by the German Federal Environment Agency. In a second project phase, it is planned to create a national network by 2013.  more...

Approximately 50% of the global population lives in cities. In 2020, this figure will be more than 60%. The success of climate protections is, therefore, dependent on energy consumption and pollutant emissions in our cities and conurbations. Local councils can specify important framework conditions for implementing energy efficiency measures.  more...

Various research projects have shown, however, that decentralised energy systems can also contribute to optimum grid operation. Here centralised control concepts are competing with systems that optimise the electricity feed-in and consumption decentrally.  more...

Steam was the first heat transfer medium to be used for distributing heat in district heating systems. This is not surprising, since steam has always played a dominant role in the power station process, so that it was easy to supply customers near power stations with steam.  more...