Zac Efron is building an eco home in Byron Bay, Australia. The Hollywood actor’s project, reported by Yahoo News UK, includes solar panels, battery storage, rainwater harvesting, and a passive solar design that minimises artificial heating and cooling. For UK homeowners, the headline isn’t celebrity gossip, it’s a checklist of upgrades that are already transforming British homes.
As Yahoo News UK reports, Efron’s home is built to operate off-grid, using a large solar array and a Tesla Powerwall battery to store energy. Rainwater tanks supply water for the property. The design orientation captures winter sun and shades summer heat, reducing the need for air conditioning.
What it costs a typical 3-bed semi
The average UK home uses about 12,000 kWh of gas and 3,000 kWh of electricity per year. A solar PV system sized at 4 kWp costs around £6,000–£8,000 installed, generating roughly 3,500 kWh annually, enough to cover most of a household’s electricity needs. Adding a battery storage unit, like the Tesla Powerwall or GivEnergy, adds £4,000–£7,000 but allows you to store surplus generation for evening use. Ofgem estimates that solar-plus-battery can cut annual electricity bills by up to 70%, saving around £500–£700 a year on current price cap rates of 24.5p per kWh.
Passive design is harder to retrofit but not impossible. South-facing glazing, thermal mass (concrete floors or brick walls), and high levels of insulation (300 mm in lofts, 150 mm in walls) can reduce heating demand by 60–90%. The Energy Saving Trust says cavity wall insulation costs £500–£1,500 and saves £200–£300 a year. Loft insulation at 270 mm costs about £400 and saves £150–£200 annually.
Grants and schemes that make it happen
The Boiler Upgrade Scheme offers £7,500 towards an air source heat pump, which works with passive design to deliver low-carbon heating. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The Smart Export Guarantee pays you for surplus solar electricity fed back to the grid, currently around 5–15p per kWh. For rainwater harvesting, a typical system costs £1,500–£3,000 and can reduce mains water use by 50%, though the payback is longer, at 10–15 years.
But the catch is that many UK homes are poorly oriented. Victorian terraces often have north-facing gardens, limiting solar gain. Planning permission is needed for listed buildings or conservation areas. And installers are in short supply, the Microgeneration Certification Scheme lists only 4,000 accredited solar installers nationwide, with wait times of 3–6 months in some regions.
EPC impact and resale value
Upgrading from an EPC rating of D to B can increase a home’s value by 5–10%, according to Nationwide research. A D-rated property worth £250,000 could gain £12,500–£25,000 after improvements. Solar panels alone add about 2–3% to sale price. Efron’s off-grid approach would be extreme for most UK homes, but the principle holds: fabric-first upgrades (insulation, glazing, draught-proofing) are the cheapest route to a higher rating, followed by renewable generation.
Officials at the Department for Energy Security and Net Zero have not confirmed when the next round of the Home Upgrade Grant opens, but the current phase runs until March 2025. Households on standard variable tariffs can apply through gov.uk from 4 November. Eligibility closes on 31 March 2027.
Frequently Asked Questions
If you own the roof or have landlord permission, yes. For flats, communal solar installations are possible but require agreement from the building owner. The Energy Saving Trust advises checking with your freeholder or management company first. Renters can ask landlords to consider the Boiler Upgrade Scheme for heat pumps, though take-up remains low.
Payback periods vary. Solar panels typically take 10–15 years to pay back via electricity savings and the Smart Export Guarantee. Heat pumps pay back in 5–10 years with the £7,500 grant. Insulation pays back fastest, often within 2–5 years. The key is to prioritise fabric-first measures before adding generation.
