©Alperia SpA (pictures of District Heating plants in northern Italy).
The next generation of energy networks Energy efficiency is a prominent global issue, with researchers looking to both develop new technologies and manage existing resources more effectively. Dr Roberto Fedrizzi tells us about the FLEXYNETS project’s work in developing a new generation of District Heating and Cooling networks that will reduce energy losses during transportation, while also facilitating waste heat recovery The current generation of District Heating and Cooling networks play a crucial role in modern society, helping to transport energy to residential buildings and businesses. However, existing networks are prone to significant heat losses, says Dr Roberto Fedrizzi. “The current third generation networks work at higher temperatures – around 90° C – than the ground level temperature. There are energy losses of around 10-20 percent during transportation,” he explains. Based at the EURAC research centre in Bolzano, Dr Fedrizzi is the Principal Investigator of the FLEXYNETS initiative, a Horizon 2020 project which aims to develop a new, intelligent, more efficient generation of District Heating and Cooling networks. “We aim to dramatically reduce the distribution temperature, and as such to reduce thermal losses through the pipeline to nearly zero,” he outlines. These fifth generation networks will be designed to work at ‘neutral’ temperatures of between 15-20°C, close to the groundlevel temperature, which is in the range of 10ºC. While this will help reduce energy losses, with obvious benefits for energy companies and other utilities, thermal energy delivered at such low temperatures is not well-suited to household purposes. “You cannot have a shower with that, or wash dishes,” acknowledges Dr Fedrizzi. A reversible heat pump will be used to increase the water temperature to a level where it can be used for domestic purposes; while this shifts the initial costs slightly 58
towards households, it will lead to longterm savings. “Where you can save money is in the energy bill that you pay, as you can reduce the amount of electricity that you use to warm up a building through a very effective operation of the heat pumps. So that’s an economic saving from the new generation of district heating and cooling networks,” explains Dr Fedrizzi. The network is also designed to deliver effective cooling, alongside this heating capability, while waste heat is recovered for heating purposes. These two aspects of
the network can work together simultaneously on the same pipeline, so that the network can operate in a way that reflects local climate conditions and seasonal demands. “There is a central unit balancing hot and cold loads. So in the summer months there will be a centralised chiller that would balance between warm and cold loads, while in winter there would be a centralised boiler,” says Dr Fedrizzi. The reversible heat pumps and chillers have proved effective in exchanging heat with the network, now
Flexynets concept of a DHC network.
EU Research
