The growing share of variable renewable energy in the grid necessitates flexibility in the electricity system. This flexibility can be provided by flexible energy generation, demand side participation and energy storage systems. Sim4Blocks developed innovative demand response (DR) services for blocks of buildings including smaller residential and commercial customers. The project implemented and tested these services in three pilot sites and transferred successful DR models to customers of project partners in further European countries.
The pilot sites are formed by blocks of buildings with a range of renewable and cogeneration supply systems and ICT infrastructure that allows direct testing of DR strategies.
Sim4Blocks’ main objectives were:
• to specify the technical characteristics of the demand flexibility that will enable dynamic DR,
• to study the optimal use of the DR capability in the context of market tariffs and RES supply fluctuations,
• and to develop and implement market access and business models for DR models offered by blocks of buildings with a focus on shifting power to heat applications and optimization of the available energy vectors in buildings.
From the activities performed to reach these objectives, the following conclusions can be drawn:
1. Technical implementation of DR with heat pumps
• It has been shown that the activation of thermal building mass can significantly increase the DR flexibility over one hour and more, by slightly adapting the room temperature in the comfort range. It has been demonstrated that the flexible operation of heat pumps in the field is possible and can be leveraged by an aggregator for multiple flexibility services or energy markets, whereas points of attention are the latency to switch on or off, the recovery time, as well as standardized interfaces, which are manufacturer and model specific.
• MPC based forecast and optimization of heat pump operation has proven to be very useful to increase own consumption from PV systems and to react on flexible electricity prices leading to an increase of self-consumption of residential dwellings by up to 40%.
• In general, it has been shown that heat pumps represent a huge potential for DR flexibility and that it is possible to manage clusters of heat pumps to respond to requests for DR flexibility.
• It has been proven that algorithms can be tailored to the particularities of each building (e.g. HP interface, HP installation, and temperature sensors).
2. Market opportunities
• It has been proven that using the flexibility of heat pumps enables balancing a BRP’s (Balance Responsible Parties) portfolio and optimization on the balancing market. Flexible operation of heat pumps in the field is possible and can be leveraged for multiple flexibility services or energy markets but using the flexibility of heat pumps for tracking a power signal such as aFRR needs to be investigated more in detail and requires a larger pool of assets than available.
• An important point of attention is the latency to ramp to full power or shut down that contradicts the general conditions of most existing markets.
• For a larger rollout, it is important to keep the costs for the connection of the heat pump control very low with standardized interfaces. As an example, smart meter gateways in Germany could provide a platform for such low-cost solutions.
• More incentives could come from PV systems running out guaranteed of fixed price feed tariffs (e.g. in Germany).