Project · Elvia and Enova
eFlow and OLTC
The eqGrid hybrid system improves voltage quality in weak distribution grids, without traditional grid reinforcement.
Energea set up the pilot project “eFlow and OLTC” together with Elvia, and is project partner in its delivery. The project develops and tests eqGrid, a hybrid solution that combines no-break tap changing with a battery system and power electronics.
The project is funded by Enova through its “Flexibility in the energy system” programme, with pilots in Indre Østfold, Råde and Spydeberg.
Energea's role
From idea to pilot project
Energea set up the project together with Elvia, and contributes as project partner throughout the project period. Per Olav Dypvik is Energea's project manager, and Frank Skoglund sits on the steering group together with Elvia.
Ten years of development behind the solution
The solution builds on ten years of development work at Energea, much of it in close collaboration with Elvia. Since the start in 2014, development has taken place together with the Swiss power electronics manufacturer Studer Innotec. eqGrid has been established as a separate company to bring the technology to market.
Controlled by energiScada™
Local energiScada™ control monitors the system and regulates eqGrid autonomously. The tap changer handles the slow voltage variations, while the battery and power electronics dampen rapid voltage changes and move current between the phases.
Elvia's aims for the project
Elvia wants to increase the available transfer capacity in weak distribution grids, avoid voltages that are too high or too low, minimise voltage unbalance, and gain a basis for practical and economic planning rules for choosing measures.
Facts
- Project owner: Elvia AS
- Project partner: Energea AS
- Project period: 2025–2027
- Funding: Enova, “Flexibility in the energy system”
- Pilots in Indre Østfold, Råde and Spydeberg
- Per Olav Dypvik is Energea's project manager
- Frank Skoglund sits on the steering group
Field results
The pilots show that the same solution can handle several of the voltage problems that limit capacity in weak distribution grids.
95% fewer rapid voltage changes
During the two days eqGrid was switched off in Indre Østfold, there were 49.3 events per day. In the corresponding periods before and after there were 2.9 and 1.4, well within the limit of 24 events per day in the Norwegian Regulation on Quality of Supply (FoL).
Voltage unbalance within the limit
At Råde, voltage unbalance averaged around 4% before the measure, with peaks above 6%. With eqGrid it stays well below the FoL limit of 2%.
In operation in 2.5 hours
The unit for Råde was built and tested in a workshop. From the crane truck arriving until the hybrid system was in operation took 2.5 hours.
Related projects and services
Voltage quality measurement
The same energiScada™ platform is used in the measurement service, from PQ meter to analysis.
Go to the service →OLTC improves voltage quality
Automatic tap changing of secondary substation transformers in Elvia's OLTC pilot.
Read more →Developing eqGrid
Commercialising the system being trialled in the pilot.
Read more →