Problem Addressed

How to enable every apartment in the UK to source energy from renewable sources as part of the UK’s pathway towards net zero carbon. A great solution to this is rooftop solar, however, a practical solution for apartments is hard to come by.

Solution Overview

The SolShare solution is simple and affordable, paving the way for millions of apartments to gain access to solar and achieving net zero. The SolShare is the world’s only hardware for connecting multiple apartments to a single rooftop solar system. This allows apartment residents across the world to enjoy the same benefits of rooftop solar that individual homes have for years: reduced electricity bills and lower carbon footprints.

The SolShare can be installed on any low to medium-rise apartment building, with major markets being Social Housing Providers, Property Developers, and Asset Owners & Managers.

The SolShare’s effectiveness can be verified and measured via the monitoring of solar distribution. This can be used to calculate each apartment’s energy savings, CO2 reductions, and money saved. Typically, apartment residents will save up to 40% on their energy bills and, depending on the size of the system, stop between 15-100 tonnes of CO2 from entering the atmosphere each year.

Allume Energy currently have systems that are supplying nearly 4GWh of electricity per year to over 1,250 apartments. These systems are stopping over 3,000 tonnes of CO2 from entering the atmosphere every year.

Launching the product in late 2020, Allume Energy are just the start of their journey. They have recently expanded to the UK and US, and have contracted sales that will treble installations: over 3,000 apartments being supplied with 13GWh of electricity and stopping 10,000 tonnes of CO2 from entering the atmosphere.

A typical SolShare system can cost £1,000 – £1,500 per apartment. That is for the entire system: panels; inverter; SolShare; labour etc.

Payback can be anywhere between 3-6 years depending on a few factors including system cost and the percentage of energy offset by the solar.

The system is built to last 20-25 years and therefore provides an ROI of 4-8 times the initial investment.

Case Study

The SolShare is suitable for any low to medium-rise apartment building. Three exemplifying case studies are given below, one from each of our major markets.

Social Housing Providers: A 66 kW SolShare system has been installed on a 44-apartment building owned by a social housing provider. The system is reducing carbon emissions by 93 tonnes per year and saving a total of £7,500 per year on electricity bills. This equates to an ROI of less than 5 years. Feedback stated “we are hearing from our residents that they don’t need to worry about electricity bills to keep warm in winter, as they have accumulated savings from spring to autumn.”

Property Developers: A 70+ kW SolShare system has been installed on a new build apartment development and connected to 39 of the 50 apartments (the SolShare can be connected to some or all of the apartments depending on requirements). This system is reducing carbon emissions by 115 tonnes per year and is saving each resident 30-40% on their energy bills. The ROI on this system was instant as it was incorporated into the apartment sale price.

Asset Owner & Manager: A 22kW SolShare system has been installed on a landlord owned building. It is connected to 12 apartments and the building’s common light and power. The system is reducing carbon emissions by 27 tonnes per year and saving the residents an average of £218 per year on their electricity bills.

Facts and Figures

40 %
3-6 years

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