The Brief Nobody Else Had Taken On
By 2013, Su-Kam’s solar project division had completed installations at IFFCO headquarters, the SBI Academy in Gurgaon, the Punjab Engineering College, Chennai Metro, Assam Rifles positions across seven northeast states, and 250KW mini-grid projects connecting entire village clusters in Uttar Pradesh. The company was the most experienced solar project operator in India’s power backup sector.
Then came a brief unlike any of those: the Indian Army wanted solar power it could take with it.
The requirement was precise and technically demanding. Military units moving through remote terrain — mountains, jungles, forward positions along the border — carried diesel generators for power. The diesel logistics chain in those environments was expensive, vulnerable, and limiting. Solar power was an obvious alternative for stationary camps. The problem was that a traditional solar installation required ground anchors, cable runs, a fixed inverter location, and installation time. A military unit could not wait three days for a solar system to be commissioned at each new position.
What was needed was a solar system that a small team could deploy in under an hour, generate useful power during the day, pack back into a transport vehicle, and move to the next location. It needed to work in dust, rain, heat, cold, and at altitude. It needed to require minimal technical skill to operate. It needed to be robust enough to survive the same transport conditions that military equipment routinely survives.
The Year of Engineering
The project took over a year from first brief to finished prototype.
The core mechanical challenge was the trolley structure itself. Solar panels are large, fragile, and aerodynamically awkward. A system that allowed them to fold compactly for transport and open reliably for deployment — without requiring tools, without creating misalignment in the panel connections, without developing structural fatigue after hundreds of open-close cycles — required fabrication and testing that went well beyond what Su-Kam’s standard solar installation work had demanded.
The electronics were, by comparison, familiar ground. The inverter and battery bank needed to be more rugged than the commercial versions, with better vibration resistance and wider operating temperature ranges. The charging management system needed to handle the irregular generation profiles of a panel that might be partially shaded or tilted off-optimal angle depending on where a camp was pitched.
The team went through multiple prototypes. Each iteration addressed failures that only appeared in the field — connections that worked perfectly in the workshop and loosened after a week of road vibration, panel mounting hardware that held in calm weather and shifted in high-altitude wind, battery systems that performed in Gurugram’s plains conditions and underperformed at two thousand metres altitude.
When Army officials came to inspect the finished system, the machine worked. The panels unfolded. The power came on. The officials went through their tests. Su-Kam passed them.
The Wind That Completed the Picture
Running parallel to the Army solar trolley project was a quieter experiment that Kunwer had been interested in for years: wind and solar hybrid generation.
The premise was straightforward. Solar panels generate power during the day. Wind is often strongest at night and in cloudy weather — precisely when solar output drops. A hybrid system that combined both could achieve near-continuous generation without storage sized for a full night of consumption.
Su-Kam completed a wind-solar hybrid project outside India — at a coastal location where the wind resource was reliable enough to make the combination genuinely complementary. The project worked well enough that Kunwer replicated it at his own farmhouse: a small windmill and a solar array running in combination, storing into a shared battery bank, running the farmhouse with minimal diesel backup.
It was, by his own account, one of the projects he was most personally pleased with. Not because of its scale — it was small — but because of what it proved. The combination of renewable sources, managed correctly, produced something more reliable than either alone. He saw in it a model for the energy systems that India’s villages, farms, and remote infrastructure would eventually need.
The technology was proven. The economics were not yet right for the mass market. He filed the knowledge away, as he had filed so many things, for the moment when the conditions caught up with the vision.
What the Defence Work Changed
The Army solar trolley did not become a mass-produced product. Defence procurement in India moves on timelines that do not accommodate standard commercial planning cycles, and Su-Kam’s financial difficulties in subsequent years interrupted what could have become a sustained defence supply relationship.
But the project left permanent marks on the organisation. The engineers who had solved the mechanical challenges of a folding solar array understood solar installation in a dimensionally richer way than engineers who had only done rooftop and ground-mount work. The quality and testing standards demanded by the Army’s inspection process were higher than commercial clients typically specified. Those standards propagated back into the commercial solar project work.
Kunwer kept the photographs of the Army inspection — officials in uniform standing around the deployed trolley, panels angled toward the sun, inverter running. In an era when Su-Kam was facing financial pressure that would eventually become the crisis that ended the company, completing a complex defence engineering project on time and to specification was evidence of something that needed to be on record.
The Army came. The machine worked. That part of the story does not change.