How is the Energy Hierarchy set to change in the new London Plan?
24 Sep 2018
With the London Plan due for its next update towards the start of 2020 and a draft consultation of changes already outlined, how might the new London Plan affect your next development?
The current version of the London Plan requires an on site carbon reduction target of 35% and already encourages developers to consider the energy hierarchy:
- Be Lean: Reduce energy demand
- Be Clean: Supply energy efficiently
- Be Green: Use renewable energy
These steps dictate construction specifications, in some instances the development layouts and of course, the build cost. Considering what we know from the draft consultation, how are these steps set to change in 2020 when the new London Plan looks to come into force?
The Be Lean step of The London Plan Energy Hierarchy aims to encourage developers to design in a way that reduces the energy demand of a development. All Energy Strategies need to demonstrate how energy efficiency measures reduce the energy demand and the new draft Plan proposes the introduction of a minimum performance target.
Under the current Plan, a development must meet the 35% carbon reduction on site, through a combination of measures. However, there are no specific performance standards for each tier of the hierarchy, so get to the 35% reduction however you can. The new plan proposes a minimum 10% reduction in carbon emissions for residential development and 15% for non-residential.
These minimum standards will require uplifts in fabric standards, including glazing specifications, lower air permeability targets and improved building services efficiency, which will likely include MVHR on the vast majority of residential schemes moving forward. Ultimately this will have an impact on build cost and will also present some challenges on heavily glazed buildings, with high heat loss.
Once a development has met the minimum carbon standard under Be Lean, developers must then consider how to provide heat and energy to a development. This means connecting into an existing district heating network where possible or providing an on site communal heat network.
The main policy driver behind this requirement is to futureproof London’s developments. This means that because a single energy centre could potentially serve thousands of homes, large scale heating system upgrades can be completed without replacing individual heating systems.
At present, the preferred technology of choice is combined heat and power (CHP), which generates space heating and electricity from a single gas fired engine. The New London Plan is introducing a revised heating hierarchy, which requires alternative technologies to be considered before assessing the viability of CHP.
These focus on zero (on-site) emission heat sources, including waste secondary heat and heat pumps. This is not to say that CHP will not be a viable option moving forward, more that the GLA are trying to drive innovation and encourage technologies that don’t use fossil fuels. With the opportunity to use new technology there is also an inherent risk of the unknown, and many developers will prefer to stick to what they know unless they have no alternative.
The Plan will also require developments to demonstrate that they will not have a negative impact on local air quality and CHP engines will require NOx mitigation to be acceptable.
A further key consideration driving the use of CHP is the new emissions factors proposed under SAP 10, which the GLA is looking to introduce under new energy planning guidance from January 2019. These emissions factors will more than half the associated carbon emissions from grid electricity, meaning that the carbon emission offset from CHP, will also be halved, making the technology less carbon efficient and ultimately less viable as a solution. On large scale scheme, financial viability of a district heating network may depend on the financial payment from on-site electricity generation, so CHP will still be considered here. However, on smaller schemes we expect a shift towards heat pump lead or hybrid energy centers to comply with the new energy planning guidance.
With significant changes to how we reduce energy demand and heat our homes under the new London Plan, you’ll need to understand how these could affect your next major London development. This will be particularly important if you’re not expecting to submit for planning permission until early 2020. Get in touch with us for a free Due Diligence review of your next site – we’ll review the Local Planning Authority policy and advise you of the potential costs and considerations for the scheme under the new London Plan.
- The current London Plan: Be Lean
- The current London Plan: Be Clean
- All you need to know about the new London Plan
Please note: This article was updated on 2 November 2018 to reflect additional guidance issued.