ARES' Nevada Demonstrator Shows Why Rail Gravity Storage Is A Train Wreck

ARES North America has been running its GravityLine solid-mass rail-gravity demonstrator at Gamebird Pit in Nevada long enough to expose the concept’s core limits, according to documents cited from Sandia National Laboratories. Sandia describes two mass cars at roughly 340 tonnes each climbing a slope of about 55% grade, using a stationary motor and chain system over approximately 36 metres of elevation. That movement stores only about 33 kWh of gross gravitational energy. The briefing notes that while the system can generate several megawatts briefly on the way down, the total usable energy stays low—raising the challenge of scaling to hundreds of MWh for grid storage.