Alfen transformer substations at innovative sharing project with water, heat and green electricity

Businesses in Belgium are increasingly working together on the generation and consumption of renewable energy. This creates Local Energy Communities: a trend that fits in with the energy transition, in which we are not only switching from fossil fuels to renewable energy sources, but also from large power plants to local energy networks. Flemish tomato grower Meer Fresh Products and nearby meat-processing company Comeco demonstrate what such a community looks like in practice using Alfen's transformer substations.

Challenge

Meer Fresh Products has had floating solar panels installed in the water basin for its tomato crop. The panels generate green energy for its own operations plus the floating solar panels offer more advantages. They reduce water evaporation, increasing water quality and cooling the water on the panels - leading to higher yields. 

Energy demand for the tomato grower is lowest in summer, leading to a power surplus during that period. For the nearby meat processor, the opposite is true. Hence, Comeco’s interest in the solar power from the nearby tomato company. It allows Comeco to make its energy supply more sustainable, without investing in solar panels. 

The companies will also exchange heat and water. For both neighbours, purchasing and selling green electricity, heat and water will save cost. Moreover, the cooperation helps make their operations more sustainable. 

For the project’s electrical engineering, they engaged Alfen, a specialist in transformer substations and grid connections in Belgium and the Netherlands.  

Solution

For this project, Alfen was awarded two partial contracts. 

1. An order from tomato grower Meer Fresh Products: Alfen is supplying 2 Diablo compact transformer stations. Alfen's transformer substations are available in a variety of capacities and configurations, making it the appropriate transformer station for any application. In the stations, green energy from floating solar panel installations is transformed from 400V to 15kV. The two stations will be connected by high-voltage cables to supply the nearby company. 
2. An order from meat processor Comeco to connect the high-voltage cable to an Alfen main station: this will provide a connection to the distribution grid and distribute the energy from the solar panels and the grid to the transformer stations.

Technical details

Alfen’s 2 compact transformer stations are: a Diabolo 30H (with a 1,000 kVA transformer) and a Diabolo 20H (with a 400 kVA transformer). 

To support the companies, Alfen manages the communications and technical data exchange between the grid company and the customers. A great advantage for the customers, who can then concentrate on their core business. 

Alfen is also installing the electrical connection between the PV installations at Meer Fresh Products and the high-voltage installation at Comeco. This is done with high-voltage cables at 15 kV and the associated control cabling. 

Because of the rather long distance - some 500 metres - between the two companies, the control signals run via fibre-optic cable, not via classic copper cabling. This is to transport signals reliably over long distances.

Rollout

Besides the electrical cabling, there are water pipes running between the farms. This allows the grower to send surplus water to Comeco during rainy periods. Piping is also laid for the waste heat generated by the grower's combined heat and power units, which can be shared with Comeco. 

The 3,000 floating solar panels generate 1.4 GWh of electricity, equivalent to an annual average consumption of more than 400 households. Comeco has calculated this will save around 600 tonnes of CO₂.