Vacant land could be used to reduce fuel poverty

Aerial view of Glasgow city centre and River Clyde

Vacant land in Glasgow could be used to help alleviate fuel poverty in the city, according to university researchers.

Scientists at the University of Strathclyde looked at the amount of derelict – or brownfield – land in the city, its proximity to social housing, and how much low-carbon heat it could yield using ground source heat pumps.

The results, published in the journal Renewable Energy, suggest that with the right technology and necessary investment Glasgow has sufficient available brownfield land to easily meet the heat demand of all households in fuel poverty.

Dr Richard Lord, senior lecturer in Civil and Environmental Engineering, said: “This study suggests there is potential to ease fuel poverty in Glasgow by making use of brownfield land to deploy renewable energy technologies such as ground source heat pumps.

“Brownfield land is a legacy of industrial retraction in many towns and cities worldwide, where land remains vacant long after it has gone into disuse, and is often a barrier to redevelopment.

Using this land for renewable heating is one option that can support development of a low carbon economy and also stimulate regeneration.”

The researchers calculated the amount of brownfield land in the city, its proximity to social housing, the likely energy yield from the technology and the heat demand from properties to reach their conclusion.

They found that Glasgow contains the greatest concentration of vacant and derelict land in Scotland, totalling 1,195 hectares over 863 sites. When combined with 367 hectares of 50 licensed and unlicensed landfill sites brownfield sites represent 9% of the city area.

In addition, Glasgow has an estimated 93,000 households in fuel poverty of which 35,000 may be at high risk. A household is said to be in fuel poverty if sufficient energy services cannot be provided for 10% of income.

Decarbonising heat

Ground source heat pumps use electrical power but produce roughly three times as much heat in return.  Scotland’s electricity is now largely from renewable sources.

Using brownfield in this way could help to address the next challenge of decarbonising heat, which has roughly double the energy demand and is currently supplied mostly from fossil fuels like natural gas.

Assuming an average household size of 92m squared and peak heat energy demand of 8 kilowatts kWt, the researchers found that if all available brownfield land had ground source heat pumps with horizontal arrays installed the entire heat demand of 34,866 properties could be met.

If only 80% of the peak heat demand is to be met, as is typical in optimising such designs, the size of this figure increases to 43,754 properties, nearly half of the total in fuel poverty.

And if more expensive vertical boreholes for heat pumps were used this would increase energy yield and hypothetically meet the demands of all properties in fuel poverty.

Dr Lord said: “It is necessary for a balance to be drawn between installation costs, the technology footprint, and the number of properties whose heat demand could be met, to provide the most cost effective, sustainable solution that still allows for future redevelopment.

“Perhaps the greatest challenges in reusing brownfield land to alleviate fuel poverty come from the inherent nature of the land itself – the fact that land is not in use may indicate that it is not currently needed or not economically viable. This might be due to location or the cost of remediation of contamination.

“It is clear that using brownfield land to provide ground source heating for social housing has the potential to contribute to alleviating fuel poverty as well as bringing significant opportunities for the restoration and reuse of vacant and derelict land.”

The research was funded by the Energy Technology Partnership, the University of Strathclyde and the BRE.