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Three steps pave the path to electrifying existing buildings

Retrofitting By Mathuran Marianayagam, Head of Building Performance Australia – 28 October 2022

Electrical engineer checking the operation of electrical control cabinet


Mathuran Marianayagam

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When the Intergovernmental Panel on Climate Change released the Working Group III report, they didn’t mince their words about the need to decarbonise existing buildings. They identified it as critical for ensuring the globe meets the trajectory to achieve net zero by 2050 (or earlier).

Unlike other concepts including carbon capture and storage, the technology and engineering know-how to convert a building to all-electric operations and eliminate on-site gas already exists and is proven to be fit for purpose. Taking out on-site combustion of gas also has benefits for human health and safety due to reduced pollutants, reduced heat loads and reduced risk of burns and so forth.

In the big picture, as the electricity supply becomes increasingly generated by renewables, the result is a dramatic reduction in greenhouse gas emissions across the entire built environment. Cundall and the Green Building Council of Australia (GBCA) have captured these benefits and outlined the existing technology options in the Practical Guide to Electrification for new buildings and its companion, the Practical Guide for Electrification for existing buildings.

The GBCA has also drawn a line in the sand – no 6 Star Green Star building now applying for a rating can include on-site gas combustion in its building services, and by 2026 the GBCA will no longer certify star ratings for projects burning gas for heating or hot water.

The National Australian Built Environment Rating System (NABERS) has also recently updated the emissions factors from NGA 1998 to NGA 2018, so buildings using a high proportion of gas will see a decrease in NABERS Energy star ratings. NABERS has also indicated that another emissions factor update is scheduled for 2030. The National Construction Code is also expected to include all-electric buildings as a deemed-to-satisfy solution in the near future.

This is good news for progressive design - but heightens the stranding risk for existing assets that use gas.

How to get started on electrifying existing buildings

One of the most common questions about existing building electrification is: where do we start? The technology is there, the theory is there, the regulations and standards exist - but what’s the critical first step?

In collaboration with the City of Sydney and the Better Buildings Partnership, we developed a toolkit that assists owners, FMs and asset managers to answer those questions and tackle the three major steps involved in mapping out the pathway to existing asset electrification at the building, precinct, or portfolio level.

First things first – the business case

Every major initiative, project or proposal in the property sector generally needs a business case, so that is the first tool to get started with. The business case tool can be used for presenting to a board or other stakeholders and forms the basis for further planning and decisions. It clearly shows, in black and white, whether the action stacks up financially in the short, medium and longer term.

The tool explains what information the business case needs to include and can be used to cut-and-paste information and details relevant to the specific asset or portfolio. As a properly structured template it also ensures the business case incorporates all the specific detail we know a board will need to see, based on our experience from working with portfolio and building owners. It also ensures the case is sound and provides the justifications for each item.

Step #2 – assess practical feasibility

With the business case sorted, the next step is to examine the technical aspects. This is where the knowledge of FMs comes to the fore, as the tool is a template for capturing a picture of what building systems and plant are in an asset, or in each asset within a portfolio. It helps make decisions around the practicalities of converting an asset to all-electric and gives stakeholders a high-level understanding of where each asset sits on the pathway of possibility.

From a technical point of view, it’s worth nothing that designing any necessary building services upgrades as part of an electrification retrofit in some ways is easier than designing them for an all-electric new building.

In an existing asset, the energy bills give quantitative data on energy use, so there are fewer assumptions necessary in designing electric systems to replace gas ones. Estimating the amount of heating/cooling/hot water demand the new electric system will need to meet is easier. By contrast, it’s always challenging to predict the demand/consumption patterns in any new building before it has humans working, living and shopping in it!

Step #3 build a timeline

The third tool helps users develop a timeline and process flow for planning works and staging electrification across a portfolio. It incorporates a 7-step guide that can help map the journey from start to final implementation of all-electric asset operation and explains the key milestone decisions and associated practical requirements and considerations.

The full toolkit has been designed to address the key concerns of each of the main parties that need to make decisions and manage critical aspects of the electrification task, from finance through to stakeholder and tenant engagement and project design and delivery.

Addressing knowledge and capacity gaps and finding ways to bring different parties together to leverage their individual skills, expertise and concerns is also very important for the wider task of reducing built environment emissions and improving urban resilience. Net zero targets are admirable – but without a workable plan, they may just be a worthy aspiration, rather than becoming an achievable goal.

“Unlike other concepts including carbon capture and storage, the technology and engineering know-how to convert a building to all-electric operations and eliminate on-site gas already exists and is proven to be fit for purpose.”