Seasonal solar-hydrogen storage for off-grid posts that run on diesel today
TL;DR Winterbank builds and runs small solar-hydrogen systems for remote sites with no grid, like high-altitude army posts and island settlements. Spare solar in the good months gets stored as hydrogen, and a fuel cell turns it back into power when the sun goes missing. Government and defence buyers pay per unit delivered.
Remote Indian sites still run on trucked diesel. Army posts in Ladakh sit at about 4,400 metres, where winter drops to minus 30°C[1]. Lakshadweep has no single grid - each island runs its own power house, and diesel generators made up most units listed as of 2012[2].
Batteries cover a night but not a snowbound week or a cloudy season. Every litre of diesel has to be hauled up mountain roads or shipped across the sea, and a storm or a snowfall can cut supply for days.
What it does, in regulatory terms: off-grid power generation with on-site compressed hydrogen storage. Hydrogen storage needs PESO approvals, and any sale of power to a third party may need state regulator clearance.
The seed pitched hydrogen storage for homes on the grid, and I've reframed it. Turning electricity into hydrogen and back returns only about 34–44% of the energy[3], so batteries and the grid win for daily cycling almost everywhere. Hydrogen earns its place only where energy has to sit for weeks and diesel is the alternative.
So Winterbank goes after that niche. A solar field, a battery for daily swings, an electrolyser, storage tanks and a fuel cell sit in one system, and the controller decides each day whether spare power goes into the battery or into hydrogen. Diesel gensets stay as the last-resort backup. Winterbank builds, owns and maintains the whole thing, and the buyer pays per unit, the way NTPC supplies the Army at Chushul[4].
The users are soldiers, island residents and remote facilities. The payers are the Army and other defence arms, union territory administrations and maybe telecom or border-agency sites, and today they pay for diesel, transport and gensets. Nobody publishes the cost per unit at forward posts, so you'll have to build that number from buyer records.
NTPC proved the concept at Chushul with a 3.7 MW solar plant feeding a 200 kW microgrid, saving about one litre of diesel for every three units generated[5]. The National Green Hydrogen Mission also names decentralised energy and storage among its pilot areas[6].
There is no public market figure for off-grid hydrogen storage in India. The firmest signal is that a defence buyer has already signed for one system, maintained for 25 years[1][4]. Lakshadweep's island-by-island diesel plants point to a second buyer type[2]. Count sites, not market size.
NTPC built the Chushul microgrid with the Army[4]. Big public companies can bid for marquee sites but they rarely chase small, scattered posts. Indian electrolyser and fuel-cell makers sell parts, not systems they run for you.
The gap is a smaller operator that can design, install and run dozens of 20–200 kW systems at sites a large utility wouldn't bother with.
| Difficulty | Hard (68/100) |
| Starting capital | ₹6–12 Cr |
| Time to launch | 18–24 months |
Honestly, everything is hard here. The kit has to work in extreme cold or salt air, sites are a pain to reach for service and buyers move through defence or government procurement. You'll also be fighting for credibility against NTPC on its own showcase.
Yes, this needs approvals, and some of them are slow.
Building this outside India? The categories above usually have a local equivalent, so check with your own regulator.
Don't let AI run the system without a manual override at the site. At a snowbound post, a bad automated call is a safety problem.
Want to work out the AI layer for Winterbank? Talk to Yash →
This is only for a team with power-systems engineering depth, defence or government sales experience and patient capital. It is not a home product and I'd never pitch it as one. Prove one thing first - that a buyer will pay a set per-unit price for a 20–50 kW pilot.
Plan for roughly ₹6–12 Cr, and an 18–24 month runway before the first system runs.
Yes. Hydrogen storage needs PESO approval, defence sites need clearances, and per-unit power sales may need a check with the state regulator.
Yes, wherever remote sites burn trucked diesel. Islands and mining camps abroad are similar buyers, so check local gas safety and power rules first.
The free Winterbank validation kit has the line-by-line capital breakdown, the effort scoring, the PESO and procurement checklist, a 14-day validation sprint with pass/fail targets, a 90-day launch plan, 10 interview questions for defence and island buyers, and 5 assumptions to test. Download the kit →
Thinking about building Winterbank or something close to it? The make-or-break work is finding a buyer who will pay what seasonal storage costs today, and that's the kind of problem I like working through with founders. If you need a hand, you know where to find me. Talk to Yash →
For illustration only. Names are fictional and ideas hypothetical; sourced facts are real but may be out of date. Nothing here is legal, financial or professional advice, and Yash Khatri is not personally liable for any use of it. Read the full disclaimer.