Bringing "Grid-Standard" Power to a Historic Tregonhawke Cliff Chalet
Perched on the rugged cliffs of Whitsand Bay, the Tregonhawke Cliff Chalets carry a unique heritage. Originally built in the 1920s and 30s as simple summer retreats for families escaping the industrial smoke of Plymouth, these “huts” have evolved into some of Cornwall’s most sought-after coastal escapes.
- Roof Mounted Array
- Off-grid System
- Affordable
- Amazing Location
The History: A Century of Cliffside Living
Perched on the rugged cliffs of Whitsand Bay, the Tregonhawke Cliff Chalets carry a unique heritage. Originally built in the 1920s and 30s as simple summer retreats for families escaping the industrial smoke of Plymouth, these “huts” have evolved into some of Cornwall’s most sought-after coastal escapes.
However, their location is as challenging as it is beautiful. With no road access and sitting far below the cliff-top mains, these properties have spent nearly 100 years relying on flickering gas lights or noisy, unreliable generators. For a modern holiday let, the challenge was clear: provide 5-star comfort in a location the grid simply cannot reach.
The Brief:
Winter-Ready Power for Weekend Stays
Our client needed a system that could handle the high demands of modern guests—think coffee machines, hair dryers, and high-speed Wi-Fi—even during the short, grey days of a Cornish winter.
The challenge wasn’t just the power draw; it was the recharge cycle. In winter, solar harvest is low, but guest expectations remain high. The solution? A “Weekly Harvest” strategy.
The Technical Specs:
We designed a bespoke system centered around Victron Energy’s industrial-grade reliability, housed in a sleek, space-saving configuration.
Solar Array: 4 x 455W High-Efficiency Panels (1.82 kWp).
The Brain: Victron EasySolar-II 5kVA all-in-one. This unit combines the inverter, MPPT solar charger, and AC distribution into one compact “blue box,” perfect for the limited footprint of a cliffside chalet.
The Reservoir: A massive 16.1 kWh Fogstar Battery.
The Aesthetic: A full electrical rewire completed in decorative surface-mounted steel conduit, blending an industrial-chic look with robust protection against the salt-air environment.
Why a 16.1 kWh Battery?
Most installers would pair a 1.82 kW solar array with a 5kWh or 10kWh battery. We went bigger.
The “Weekly Harvest” Logic: During a Cornish winter, a small solar array might only produce a few kilowatt-hours per day. By installing a 16.1 kWh Fogstar battery, we created a massive energy “buffer.”
Monday to Friday: While the chalet is empty, the 1.82 kW array trickle-charges the battery, slowly filling the 16.1 kWh reservoir over five days.
The Weekend: When guests arrive on Friday evening, they have a “full tank” of energy ready to go. This allows them to use the 5kVA inverter for high-draw appliances (kettles, toasters, hair dryers) without worrying about the sun’s position.
The Summer Benefit: In the summer months, the solar generation is so ample that the battery is usually back to 100% by midday, providing limitless power for daily use.
The Result: Invisible Technology, Visible Comfort
By combining the decorative steel conduit rewire with the silent Victron system, we’ve transformed this historic Tregonhawke hut into a high-end, energy-independent retreat.
The owners now have a property that can be hosted year-round on platforms like Canopy & Stars, providing guests with the magic of the Cornish coast without the compromises of off-grid living. No noise, no fumes, and—most importantly—no power trips.
The “Cliffside” Verdict
The Victron system pays for itself in just 15 months.
Beyond the cash, the “Soft ROI” for a Tregonhawke chalet is even higher:
Zero Noise: Guests at Whitsand Bay pay for the sound of the ocean, not a 5kW engine.
Zero Logistics: You no longer have to carry 3,500 litres of petrol down the cliff path every year.
Guest Safety: No petrol storage on-site reduces fire risk, which is a major concern for cliffside timber structures.
Financial Performance and Payback of the Solar & Battery System
✔ Payback achieved in 15 months!
| Investment Category | Victron Solar System | 5kW Petrol Generator |
|---|---|---|
| Upfront Cost (Installed) | £8000 | £800 |
| Annual Fuel Costs | £0.00 | £5,431 |
| Annual Maintenance/Parts | £0.00 | £300 |
| Total Year 1 Cost | £8000 | £6,531 |
| Total Year 2 Cost | £0 | £12,262 |
| Break-even Point | 15 Months (Approx. 1.25 Years) | |
| 10-Year Potential Savings | £49,310 in avoided costs | |
Bringing “Grid-Standard” Power to a Historic Tregonhawke Cliff Chalet
Discover how Offgrid Western brought 5-star power to a historic Tregonhawke Cliff Chalet using a Victron 5kVA system and high-capacity Fogstar battery storage.
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