Allume Energy’s world-first SolShare rooftop solar technology

A world-first technology by Australia’s Allume Energy is revolutionising the way solar power is delivered. It's addressing energy equity by cutting power bills, and bringing clean energy to apartment dwellers.

Allume’s award-winning SolShare solution allows multiple apartments in the same building to share a single rooftop solar PV system. The technology is easy and affordable to install and manage, making it a popular choice for housing associations and property developers.

It reduces carbon emissions by up to 28 tonnes a year for a typical apartment block. Best of all, SolShare can cut energy bills by up to 40%, generating long overdue savings for households living in apartment blocks, and is especially impactful to those living in social housing.

SolShare is installed in Australia, Germany, the US and the UK. Globally, the company has sold over 350 SolShare units and has another 10,000 units in the pipeline. In February 2023, it completed the first installation of SolShare for the UK’s social housing sector in Wales.

‘We’re on a mission to make rooftop solar accessible for everyone,’ says Allume’s Co-founder and CEO Cameron Knox. ‘More than 2 million Australians, 15 million Americans and 300 million Europeans live in apartments. There’s no way to achieve net zero or even get close to it if you’re not offering them a feasible renewable energy option.

‘Unlocking rooftop solar is the cheapest and fastest way to decarbonise and reach net zero. We feel we can make an enormous, long-lasting impact.’

Bringing affordable rooftop solar to apartment buildings

The idea for SolShare came when Knox was tasked with finding a rooftop solar system suitable for community housing. He found most products were expensive and not accessible to cash-poor organisations.

‘We looked worldwide for a single rooftop solar system that could be shared by multiple apartments,’ says Knox. ‘When we couldn’t find any, we decided to develop it ourselves.’

The physical component of the SolShare technology is a distribution box that directs solar energy to multiple apartments simultaneously. It optimises the solar delivery based on who needs the energy at any point in time. Its ‘dynamic sharing’ algorithm ensures every apartment receives the same amount of solar over the course of the month.

Each SolShare unit can support up to 10 (US) or 15 (Australia and the UK) apartments. It is modular to cater for larger apartment numbers. Tenants can choose whether or not to sign up for solar energy and pick their preferred energy retailer.

Going global from the start

After 3 years of development, Allume launched SolShare in 2019. Today, SolShare is installed in around 2,000 apartment units in Australia.

Allume took SolShare global early because of ‘the international nature of the problem we’re trying to solve,’ says Knox. ‘We entered the US in December 2021 and have completed 50 installations to date. We also entered New Zealand in 2022 and are working with Kāinga Ora, the country’s public housing authority, on new-build projects.

‘We just did our first installation in Germany. We expect most of our revenue to come from overseas markets over the next few years.’

First installation of SolShare for the UK’s housing sector

Allume’s fastest-growing market is the UK, which it entered in 2022.

SolShare is certified by the MCS, the organisation that certifies low-carbon energy technologies and contractors. SolShare is currently the only solution in the market to comply with SAP 10.2 PV credits, the newest release of the UK’s Standard Assessment Procedure (SAP). Social housing providers and property developers can use SolShare to increase a flat’s SAP score by between 5 and 15 points, increasing the EPC ratings of apartments. SolShare is fully compliant for installation by all UK distribution network operators.

In February 2023, Allume, Wales & West Housing and the Welsh Government announced the first installation of SolShare technology for the UK’s social housing sector. The project connected 24 flats, increasing each flat’s SAP score by 15 points. SolShare has the potential to meet 55%–75% of each flat’s electricity demand. This could equate to an electricity bill saving of around 50% (between £390 to £530) a year, per household.

Allume’s success is set to increase. The UK’s energy regulator Ofgem has recognised SolShare under the ECO4 funding initiative. The scheme provides funding to help eligible households reduce the cost of heating by installing energy-efficient measures.

SolShare was recognised as an ‘innovation measure of substantial uplift’ under this scheme, meaning it has demonstrated a significant improvement over comparable measures. The innovation status is more than just a label. It enables 45% more funding to be granted to projects that include the SolShare.