Lidl’s distribution centre has the most effective internal energy storage and micro-network in Finland

Sweco’s industry experts designed a smart electricity network, which uses exclusively renewable energy, for Lidl’s distribution centre in Järvenpää. The enormous property is heated and cooled with the solar panels of its own micro-network – auxiliary power systems and purchased energy are used only when necessary. Self-sufficient electricity production is possible thanks to the new energy storage technology.

Lidl’s micro-network includes medium-voltage and low-voltage switchgears, 1,600 solar panels, two auxiliary power systems, and, at the heart of it all, the most effective energy storage attached to a property in Finland.

“We were responsible for the preliminary planning and implementation planning of the joint operation and the energy storage control of the various entities in the electricity distribution within the micro-network, meaning how everything related to electricity distribution should work in different situations,” says Marko Räty, Sweco’s expert on smart electricity networks.

The energy storage technology is state-of-the-art in Finland. Before this, a similar solution had only been used in connection to a property in the Sello shopping centre and in Fortum’s testing environment. The design team for the latter also included Sweco. “At the moment, the energy storage of the distribution centre comprises Finland’s most powerful set of accumulators attached to a property and connected to the reserve market.”

Significant benefits achieved through expert choices of equipment

Sweco’s industry experts also took care of the procurement materials for the aggregates and contract work.

“We have extensive experience of technical configurations and selecting equipment for smart micro-networks. Our experience guarantees that the solutions are reliable, the products are safe and the cold chain remains uninterrupted,” says Mika Kierikka, Sweco’s expert on circular economy. The right choices of equipment also enabled significant savings for Lidl. “With detailed configurations, we were able to skip the most expensive energy storage solution and choose a corresponding, less expensive system, instead. This solution will pay itself back tenfold,” Räty says.

Electrical energy is consumed and stored flexibly

Thanks to the multi-directional transmission capacity of the micro-network, the distribution centre’s internal production and consumption of electricity are automatically optimised around the clock, according to factors such as the duration of sunshine and the price of electricity.

“The distribution centre produces energy primarily with its own solar panels, and energy is stored for later use whenever possible, which makes the entity as self-sufficient as possible in terms of electrical energy,” Räty states.

The micro-network of the distribution centre is an example of decentralised energy production, which is based on producing electricity in multiple small units instead of traditional power plants. Independent control over the energy consumption makes correctly-timed consumption possible. The distribution centre participates in demand response by controlling its energy consumption so that spikes in the consumption are reduced.

“The spikes can also be reduced with energy storage, which is one of the most effective earning models.”

The distribution centre operates on Fingrid’s reserve market

Traditionally, properties only receive energy. However, the micro-network of the distribution centre has a two-way connection to the national electricity grid. The energy from the storage can be transmitted outwards, which allows the centre to operate on the reserve and balancing electricity market of Fingrid, the company responsible for Finland’s main grid.

“The distribution centre’s operation on the reserve market balances the fluctuating load on the main grid, which means that the frequency balance of the main grid’s normal state is maintained in a two-way fashion,” Räty says. Participation in the market can also help if a severe malfunction occurs in the main grid. “Power can be fed from the property into the grid, or the distribution centre can use its own energy sources when needed, such as the auxiliary power generators or the energy stored in the accumulators.”

Balancing the main transmission grid will become an increasingly significant challenge in the future. Power plants that maintain and strengthen the inertia that is vital for the grid will be complemented with an increasing number of more uncertain, local means of energy production.

“The use of solar panels and wind power will grow, and the proportion of adjusted use in the industry will also grow. All of this will lower the inertia in the electricity grid even further.”

Top-class reliability!

The distribution centre operates around the clock and contains as much as 20,000 square metres’ worth of different types of cold facilities. The volume of the distribution centre means that no compromises can be made on the reliability of the electricity network. Fortunately, the energy storage technology also improves the quality of electricity.

“The accumulators in the energy storage filter things such as harmonic components and compensate for reactive power, which reduces the losses in the electricity network and raises the reliability to the highest level,” Räty says. Outages in the distribution network can be dealt with seamlessly, and the auxiliary power systems may not even need to be started during all malfunctions. “In practice, the energy storage technology can be used to lower the energy costs.”

The micro-network project in Lidl’s distribution centre is a true trendsetter in the field of renewable energy usage and correctly-timed energy consumption. Energy conservation can be achieved through increasingly innovative means.

“Electricity systems that are complex yet reliable are our specialty, and Lidl’s distribution centre offered us an excellent opportunity to introduce new, industrial-level electrotechnical expertise and an unbiased perspective into the electrisation of properties. It’s great to be a part of the future of electricity networks!” Räty says, summarising the project.