Batcave (Järvenpää power plant)
Operating, 2 MW · 1 MWh, in Järvenpää, owned by Fortum. Every fact below is as a published source states it, with the address beside it; a field not shown is one no source gave, and nothing is guessed.
The battery
| Power | 2 MW |
| Capacity | 1 MWh |
| Duration | 0.5 hours |
| Status | Operating, as of 1 March 2017 |
| Owner’s date | 1 March 2017, actual |
| Municipality | Järvenpää |
| Placed on the map | at the centre of Järvenpää, its municipality (GeoNames) |
Who is behind it
| Owner | Fortum |
| Built by | Saft (battery supplier) |
| Business ID | 1463611-4 |
YTJ, by exact name: Fortum Oyj. Fortum's release names "Fortum", not a subsidiary. https://avoindata.prh.fi/opendata-ytj-api/v3/companies?businessId=1463611-4
Not published anywhere we have found: ultimate owner, developer, cells. The page says so rather than guessing.
What the sources say
Taken into use on 1 March 2017 at Fortum's Järvenpää power plant (Fortum). About 6,600 lithium-ion cells. Fortum names Saft as the battery supplier; it does not say who made the cells, so cell_maker is blank. No later source read says whether it is still in service.
Evidence and sources
From the owners’, developers’ and builders’ own releases, council decisions and permit bulletins, read by Vitreous and checked against the owners’ own words on 12 October 2026; a bracket such as “(Energy-Storage.news only)” in a field means the trade press is still the only source for it. Fingrid publishes no meter, no price and no instruction per battery, so this page carries no money: what one megawatt is paid in Fingrid’s markets is on the markets page, for the whole market and never for a named battery. List id FI-B001.