Energy Quality Management

Energy Quality Management EQM is the planning, designing and operation of energy sources, conversion distribution and end use in the energy system with the aim to conserve the energy quality in the best possible way in each step of the project. Electricity and fuels are high quality energy while a large part of our energy use e.g. space heating and domestic hot water, is low quality. With improved energy efficiency in the end use of the energy, we can reduce our need for fossil fuels far beyond what energy conservation alone can do.

Energy quality

The quality of energy is defined as the relative amount of mechanical work that can be generated in a theoretical conversion process. In the literature we can find several terms that refer to the mechanical work content of a certain quantity such as the exergy or availability. Analysis based on this concept can be called exergy analysis or second law analysis. This refers to the basic thermodynamic laws of energy where the first law tells us that the energy is always conserved while the second law tells us that all irreversible processes increase the entropy of the total energy of the system or in other words the quality, or the ability of the energy of the system to generate mechanical work is lost. Since energy demanding processes require energy quality on different levels minimum loss of quality for one process will make the energy flow useful for other processes. As an example we can take the refurbishment of a house from the sixties with electrical heating. With better windows, insulation, air tightness hand heat recovery we can rather easily reduce the energy for space heating to one third. But we could still be using electricity that has very high quality, since it can almost 100 % be converted to mechanical energy, to provide heating to the room at a very low quality level. If we instead use a heat pump which can generate 3 times more heat at low quality than the electricity put in the total electrical energy needed has been reduced to 1/9 of the output.

Figure 1. The need for high quality energy can be radically reduced with good energy quality management along with energy conservation.

Until now our energy systems have been resource driven. We identify sources, generate energy products and build up a system to store and distribute them to an end user market. The result of this is that our focus is on resources with the highest revenues that logistically can be stored and distributed freely and will easily find its market in new energy based services and higher degree of individual mobility. Fossil fuels, oil, coal and gas, are products that best meet the above criteria. The best available technologies, possible sources of energy, the planning and the management of an urban energy system together with the development of societal needs are instruments that have to be tuned together to meet the sustainability criteria. It can be demonstrated how a general system approach based on these components can lead to more cost efficient solutions to meet the challenges of climate change.

Figure 2.  The community energy system consists of a large set of energy sources and terminal energy use with multiple systems for transfer of energy from the sources to the end users. With co-generation or tri-generation and also when waste energy from processes is utilized as energy source for other low valued processes the complexity of the system is increased.

It is not only the energy use of the building, which is of importance for good energy economy but also the interface of the building energy system so that we have flexibility in the choice of the energy supply system.

There are many good examples in the Nordic countries showing how the interconnectivity of users and processes can contribute to considerable energy savings and environmental benefits. Waste heat from industrial processes and data storage facilities has been successfully used for heating buildings.  We have examples of how cooling energy from data storage is used as a source for a district heating system. The biggest challenge is, however, not to identify downstream loss of energy that can be useful for other processes but the logistics, or how to transfer the energy to where it is needed. The development of district heating networks is an excellent example where the systems were primarily built up for distribution of heat that is generated by burning fossil fuels, which have been gradually replaced by cogeneration heat, heat produced by heat pumps, heat generated from biofuels and from burning waste etc.

The purpose of the workshop is to demonstrate cases where EQM has been successfully used in the Nordic countries and internationally. To invite researchers and developers to put forward new technologies and concepts that can enhance the use of EQM. Also to identify the potential for use of EQM in energy system development and energy planning, to discuss policy issues and how this can help to meet the targets for greenhouse gas emissions.

The conference does not address energy efficiency in general and priority will be given for presentations that address the energy quality issues on system level rather than component performance.