- Cost to comply with emissions reduction targets to increase for developers who traditionally specified gas, in particular gas CHP, and decrease for those specifying shared ground loop array ground source heat pumps.
- GLA heat pumps report identifies shared ground loop arrays with individual ground source heat pumps as the lowest carbon & lowest cost solution for heating new builds.
- UK cities taking action to be zero-carbon by 2050 – some even earlier.
- Simultaneously house building to increase by 300,000 every year to 2020.
- Low carbon heating plays a critical role in delivering zero-carbon ambitions.
- London developers to build to SAP10 emission factors from January 2019.
It has been widely reported that urgent action is needed to avoid the irreversible and catastrophic damage that temperature rises due to global warming are set to bring.
Homes and workplaces in London account for 78% of its greenhouse gas emissions. To deliver its ambitions to be a zero-carbon city by 2050, the carbon intensity of heating is a critical factor for London developers, who are required to achieve 35% reductions beyond the TER in Building Regulations, and pay to offset any residual emissions.
To cost-effectively develop the tens of thousands of homes required in the UK whilst adhering to uncompromising zero carbon ambitions, a solution in the form of ground source heat pumps (GSHPs) with Shared Ground Loop Arrays (SGLAs) is coming to the fore. The result is a transformed and future-proofed clean heating infrastructure to rival and replace the gas network.
The Greater London Authority (GLA), ‘Low Carbon Heat: Heat Pumps In London’ report concludes that shared ground loop arrays, pioneered by Kensa – defined by Etude as a ‘communal ground loop connected to individual heat pumps’ – are ‘the most efficient, lowest carbon, and lowest cost solution when utilised in new build houses compared to various air source, direct electric, gas and CHP configurations’. (Read Kensa’s review of the GLA’s report here). The report continues:
The communal ground loop with individual heat pumps appears to be the most economic solution of all (at approximately £500/yr) and is also compliant with London’s key objectives in terms of air quality and carbon emissions. It combines several advantages: it is very energy efficient and does not require dedicated heat metering and billing.
Owing to GSHPs efficiencies, by more than halving the CO2 emission factors for electricity in the proposed SAP10 (effective as of January 2019 for for all new planning applicants in London), the carbon saving for ground source compared to a gas combi boiler would be 70.9%. For a best practice scenario, developments featuring 10% fabric efficiencies plus 25% additional energy efficiency measures such as solar PV and heat recovery ventilation, alongside a GSHP, would result in a carbon offset price of £871. Compare this to a gas combi boiler where the carbon offset price would be £2,992, equating to a saving of £636,300 on a 300 unit development.
As the UK grid becomes increasingly decarbonised, as is Government’s ambition, the carbon savings of electricity and therefore GSHPs becomes even greater, as Etude’s report affirms:
Heat pumps offer an immediate and significant reduction in the carbon content of heat today and this advantage increases substantially in the future as the electricity grid decarbonises.
The impact of changing carbon factors means the cost to comply with emissions reduction targets increases for developers who traditionally specified gas, in particular gas CHP, whilst it becomes cheaper for those specifying, and using, shared ground loop array ground source heat pumps.
In this comprehensive blog post, Kensa examines how choices of heating systems can save zero-carbon city developments several tonnes of CO2 and also tons of money in offset funds, too.