The EU needs more renewable energy sources, but the Sun and wind’s unpredictability means that the electricity ecosystem must become more flexible. Empowering consumers can play a major role in electric grids’ flexibility.

Because buildings’ energy use levels aren’t constant, national electricity grids always have to seamlessly balance supply with this fluctuating demand. If this load management isn’t properly carried out, it could lead to higher costs, wasted power or power outages. The increasing use of renewable energy sources further complicates supply and demand. Electrical energy can’t be easily stored and renewable sources don’t produce a continuous predictable output such as when the Sun doesn’t shine or the wind doesn’t blow. Demand needs to be adjusted since supply can’t be easily controlled. This process is known as demand response (DR). It involves shifting electricity use from times with little renewable energy production to when there is more. DR has great potential to make electricity grids more flexible.

Making the most of renewable energy sources

The EU-funded Sim4Blocks project tested DR in blocks of buildings. By looking at blocks rather than single homes, it examined more ways of applying DR, from individuals living in the home to transmission system operators who ensure energy systems’ stability. “The focus was on the development of innovative DR solutions for smaller residential and commercial customers,” explained coordinator Wolfram Mollenkopf. “The project combined decentralised energy management technology at the building block scale to enable DR.” The Sim4Blocks team tested DR systems and services at three pilot sites in Germany, Spain and Switzerland. The sites were blocks of highly energy-efficient buildings with different energy systems and regulatory conditions. The natural fluctuations of renewable energy sources were considered to adapt the electricity consumption to the supply. A special feature of the Swiss and German pilot sites was that a local heating network supplied a building cluster with decentralised heat pumps. The aim was to optimise the operation of the heat pumps in terms of flexible electricity tariffs, participation in power markets and photovoltaic electricity self-consumption. At the Spanish site, team members determined the optimal electricity consumption for residents of a large residential building complex by using self learning algorithms.

Innovative energy management

To flexibly operate heat pumps, project partners developed and tested software prototypes, optimisation algorithms and their corresponding interfaces for intuitive user interaction. At the German site, they rolled out an app to increase self-consumption in municipalities. At the Spanish site, a second app was created to present potential monetary savings for residents while encouraging them to control their electrical loads. Results showed that the heat pumps have huge potential for flexibility, but until now uniform interfaces were missing. In addition, it’s possible to manage clusters of heat pumps by an aggregator to deliver negative reserve power. An aggregator is a business entity enabling smooth cooperation between a system operator and small customers to trade electric power. Overall, acceptance of the new technology by residents was promising, but bigger incentives are needed to boost participation levels. “By widely implementing load management, more renewable energies can be better integrated into the electricity mix while requiring smaller investments in grid infrastructure,” concludes Mollenkopf. “Better awareness of and engagement in energy use in blocks of buildings will lead to electricity price savings and less grid usage charges.”