Do you want to meet your electricity and heat needs with the help of solar panels, even when the sun isn’t shining? It is possible thanks to thermal solar panels, or PVT panels, which act as an energy source for the heat pump. By connecting those panels to a heat-cold storage (ATES), you can also use the stored heat at other, less sunny times. The decentralized solar heating network developed within the TKI project DeZONNET therefore offers all kinds of advantages over other electrical systems. How can you provide homes in existing neighborhoods in the Netherlands with their energy needs? And in particular: what to do with the heat demand? For project leader Sabine Jansen, assistant professor of ‘Sustainable energy in the built environment’ at TU Delft in daily life, the main challenge lay in the question: how to realize the energy transition at neighborhood level as locally and sustainably as possible. Not only for new construction, but also for existing construction. Such as pre-war neighborhoods with those typical 1930s houses: poorly insulated and without the presence of an external, sustainable heat source.
Solar heat network - De Zonnet
Electricity, heat and hot water: three times the charm
You have sun everywhere. The only question is: how can you make the best possible use of the available, often limited roof surface? Even when the sun isn’t shining? And store the heat or energy generated with it? For example, Triple Solar, one of the consortium partners within the TKI project DeZONNET, came into the picture alongside Deltares, Greenvis and WarmteTransitieMakers. The company is considered a leader in the manufacture of PVT solar panels. Triple: the word says it all. Triple Solar’s solar panels are provided with a thermal layer and a heat exchanger at the back, with which you can meet three needs at the same time: electricity, heating and hot tap water. “You can even add a fourth application, namely cooling in the summer,” explains Cees Mager, managing director of Triple Solar. “The panel we developed is linked to a heat pump. Normally you can get energy from the ground or the air. We have added a third source to this: sun and daylight. The PVT heat pump panels act as the energy source for the heat pump. By connecting those panels to a heat-cold storage (ATES), you can also use the excess heat stored in the summer at other times. Like in winter, when the outside temperature is low. “
The link with the thermal storage system means that a lot of roof surface is not required, says Mager. “For an average household, 12m2 PVT surface is enough. This means you are already energy neutral with regard to heating. The system is therefore designed in such a way that in principle you do not need company roofs for it. It is aimed at the neighborhood level, whereby the individual houses are connected to each other using a smart thermal grid. “Jansen:” The innovative character of the project lies in the combination of individual heat generation with PVT and a very low-temperature heat network. The research focused on the optimal operation of the system: when is the generated heat used immediately, when is heat supplied to the grid, and when is it extracted from the grid. This is to make the system as efficient as possible. In addition, an innovative delivery set has been developed that makes the necessary controls possible. Finally, we looked at the total cost of ownership and possible market models. The results are optimistic. The calculations we performed yielded an efficiency rating (COP) between 6 and 7, whereby the homes do not necessarily have to be insulated to label A. That is quite high. “
Demo project: technology and residents
The concept will soon be tested as part of a demo project in The Green Village at TU Delft. Mager: “We are going to set up a test installation there on a replica 1970s-type house. We expect to be ready with this this summer. “In addition, work is being done on the application in a neighborhood in Haarlem: the Ramplaan quarter. The residents of that neighborhood were intensively involved in the process during the project, and recently voted positively about the further development of this system for their neighborhood. Jansen: “The decentralized solar heating network that we developed within the framework of DeZONNET is a completely new concept, in which individual households together generate the necessary heat for the neighborhood. Which means in practice that not all residents need a suitable roof surface. Residents have to figure out how to settle the revenues in a collective context at neighborhood level. This can be done through a district energy company or neighborhood cooperative, for example. Some residents may also want to arrange everything themselves, while others want to be relieved as much as possible. “Read more on our Heat network page with more information about heat networks, solar heat network and ATES regeneration. Source: