Monitored case study · Commercial three-phase mini-grid
Reliable off-grid power for a working forestry site.
A remote Scottish forestry and training site required dependable three-phase electricity without a mains connection. Machinery, operational loads and business continuity made this a different engineering problem from a domestic off-grid home.
The challenge
Keep control of the power and the site.
Bringing mains electricity into the woodland could have meant overhead cables across a working forestry site. That would have introduced hazards for machinery, restricted planting and involved neighbouring landowners.
The new workshop needed lighting, roller shutters and three-phase machinery. Training activity and future site growth also had to be allowed for from the outset.
Once the system was commissioned, the separate welfare building could be connected to it. The small generator that had previously run all day for the kitchen, toilets and office could be switched off.
The engineering decision
A commercial mini-grid with meaningful peak capacity.
The system combines a 43 kWp solar array, 91 kWh of battery storage and 45 kVA of three-phase inverter capacity. It had to support working machinery and three-phase loads at a site where interruption carried real operational consequences.
Remote monitoring and control are part of the architecture, providing the visibility needed to manage a system located far from conventional grid support.
“We were very surprised when we first spoke to Ian, particularly that we could get three-phase.”
System architecture
Designed as site infrastructure.
Recorded operation · Calendar year 2025
Performance visible in use.
The monitoring record shows 11,765 kWh supplied to site loads in 2025. Of that delivered energy, 42% came directly from solar, 55% from the battery and 3% directly from the generator. No grid import or export was recorded.
The solar array routed 11,865 kWh to loads and batteries. The generator also sent 4,948 kWh into the battery. The 97% solar-or-battery delivery figure therefore describes the route by which energy reached the loads, not a verified renewable share.
Source: VRM 15-minute energy export, 1 January–31 December 2025. Figures are rounded. Missing channels were not estimated. Battery output is counted once when delivered to loads; energy previously used to charge the battery is not counted again as generation.
Delivery route, not renewable share: battery output can include energy previously supplied by the generator.
“We're delighted to be in a position here where we're in control.”
Victron Energy project film
Hear the Scottish Woodlands story.
See the installation, the machinery test and the client interviews.
Watch on YouTubeRole and attribution
Designed by Ian Hewson.
Ian designed this system while a co-founder and director of Off Grid Engineering Ltd. It forms part of his personal engineering record and monitored evidence base.
Remote or three-phase project?
Establish the load, resilience and control strategy before specifying equipment.
Commercial off-grid systems must be designed around operational consequences as well as annual energy demand.
Discuss your project