Last edited 20 Nov 2017

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CatClarkson Engineer Website

BREEAM Reduction of energy use and carbon emissions

Contents

[edit] Aim and benefits

This issue rates how well buildings have minimised energy demand, primary energy consumption and CO2 emissions. It only covers regulated energy (pre-2018), and so excludes external lighting, small power, and specialist equipment.

The aim of this credit is to encourage designers to take a holistic view to an efficient energy strategy in a building, rather than solely reducing energy (ENE 4 Passive Design) or replacing fossil fuels with renewables (ENE 4 LZC Feasibility).


[edit] What's the difference between the ENE 1 credits scored and Part L?

Part L is concerned solely with reducing CO2 emissions from a building. While there are limiting factors (e.g. minimum fabric efficiencies), it is entirely plausible to have a building that uses a large quantity of energy but off sets it all with renewables to comply with building regs.

ENE 01 balances reducing operational energy demand, primary energy consumption and CO2 emissions to give an "Energy Performance Ratio". The three graphs below show the the energy performance ratio given for each of these three elements for the percentage improvement over a notional building as read from the BRUKL compliance report. These figures apply to ENGLAND ONLY. This varies per country to account for the fact that some country's building regulations are more stringent than others.

Ene1 methodology.PNG

The EPR for each element, is then added up to give an overall EPR which is compared to the ENE 01 credits table in the BREEAM manual. The ENE 01 calculator/scoring and reporting tool does this all for you, but sometimes it's handy to know the background. A spreadsheet has been included in the tools and resources section which contains the above graphs, if you find it helpful to get your head around the calculation.

As always, please only use official, up to date, BREEAM tools for calculating credit requirements etc.

So, as an example, if you have a building that uses a lot of energy for building services and doesn't have especially efficient fabric (e.g. only just meets building regulations for Primary Energy Consumption and Energy Demand), then the maximum credits you can get, regardless of how much energy offset by renewables is 5 UK New Construction 2014 credits. Note, in previous schemes additional requirements may mean 5 credits are not achieved.


[edit] When to consider

In the UK, RIBA Stages typically guide when things get done on a project. Standard RIBA Stage deliverables are as follows:

[edit] RIBA Stage 0 and 1

These stages are "Strategic Definition" and "Preparation of Brief". It's unlikely you'll get any solid information during these stages regarding credit targets. However, if your client has said that energy efficiency is a main priority for the project, you can probably assume you'll achieve more credits than if they're happy to scrape through building regs.

[edit] RIBA Stage 2

This stage is "Concept Design". Standard RIBA Stage 2 deliverables at this stage include conduction an initial Part L appraisal. While this might not finalise the number of credits you'll actually achieve (there's a lot of design changes to go yet!), it should give you a reasonable idea.

[edit] RIBA Stage 3

"Developed Design". An interim Part L report is often a deliverable from this stage. This will give you a better idea of the number of design stage credits you'll achieve. This may be the final Part L design stage report you get, depending on whether there are further design changes during RIBA Stage 4.

[edit] RIBA Stage 4

"Technical Design". At this stage, a full "as designed" Part L report should have been produced, and submitted to building control for approval. The report which is submitted to building control is pretty "safe" to use as your design stage evidence, providing it meets all criteria etc.

[edit] RIBA Stage 5

"Construction". Try to keep an eye on design changes as best as possible. If there's anything big relating to building fabric, heating/cooling systems or renewables ask for confirmation that there is no effect on Part L from the engineers.

[edit] RIBA Stage 6

"Handover and Close Out". Typically expect the final "as built" Part L report within about 30 days of practical completion.

[edit] Step by step guidance

[edit] Questions to ask while seeking compliance

[edit] Tools and resources

Guidance note explaining ENE 01 Methodology

Spreadsheet helping to explain ENE 01 Methodology for ENGLAND

BRE Knowledge Base related articles

[edit] Tips and best practice

Tip: Don't assume that a lovely fully naturally ventilated building will score better than a glass mechanically ventilated sky scraper. This credit still relies on a percentage improvement against a notional building. So as long as your mechanically ventilated glass box is better than the notional mech vent glass box, you can still score well in this credit (albeit you may score lower elsewhere).

--CatClarkson


BRE Global does not endorse any of the content posted and use of the content will not guarantee the meeting of certification criteria.


[edit] Find out more

Performance gap between building design and operation

Part l

Renewable energy

Zero carbon building

Energy performance certificate EPC

Carbon emissions reduction target

BREEAM Passive design

Passive design