How Grosvenor cut emissions by a quarter
The developer reported a 24% carbon reduction in its latest net zero progress report. Here is how it reached that point and what comes next.
Grosvenor’s emissions at a glance
- 59.1kt CO2e: total emissions in 2019 (baseline year)
- 44.6kt CO2e: total emissions in 2021
- -17%: fall in building emissions
- 200kg CO2e/sq m: embodied carbon in recent retrofit projects (far below 500kg CO2e/sq m target)
- 35%: target for percentage of suppliers who will report emissions to Grosvenor by the end of the year
How Grosvenor cut emissions in its historical portfolio
Building emissions in 2021 were down 17% on 2019, Grosvenor’s baseline year. The developer’s progress report said this was partly due to lower occupancy at the start of 2021. But Grosvenor is also ramping up a £90m retrofit programme.
Early priorities for the programme include getting rid of gas boilers in the portfolio’s biggest buildings. Last year, Grosvenor retrofitted five office buildings on Buckingham Palace Road in London, putting in solar tiles on the roof, changing the heating systems and adding secondary glazing and energy efficient lighting.
On average, Grosvenor’s interventions have upgraded buildings’ EPCs from about a D to a B, according to Andy Haigh, Grosvenor’s director of climate positive solutions.
Retrofitting “is not rocket science”, Haigh says. The big, easy wins are often the obvious ones: moving from gas to heat pumps, replacing out of date lighting, improving glazing, adding building system controls.
In fact, because so much of the portfolio is listed, there is little Grosvenor can do about the structure of the buildings. Instead, it’s about driving efficiency inside.
What tools does Grosvenor use?
Grosvenor uses Demand Logic, a software provider that tracks how parts of a building operate, whether that’s the HVAC system, energy use or metrics such as temperature and carbon dioxide.
Having recently invested in Demand Logic, Grosvenor is “massively” rolling it out across its portfolio. Haigh says the platform is useful in buildings that don’t have “big smart BMSs” in tenanted areas because it provides devices you can simply clip onto existing cables.
At Eccleston Yards in Belgravia, London, Demand Logic helped identify ways to cut buildings’ energy use by 35%.
He says: “That’s huge. There are still lots of low hanging fruit that we’re starting to unpick, but obviously, if you don’t have the data you can’t target your savings.”
At the moment, the developer targets buildings (or units within a building) when they become vacant. In between lease agreements, they can make necessary upgrades.
“I think what’s going to become harder in time is that we’re going to have to start retrofitting buildings where tenants are still occupying them,” Haigh says. That will have to involve greater co-operation, including green clauses in leases.
New leases will require tenants to provide the developer with energy performance data. That will be a gradual process as tenancies come to an end and leases get renegotiated. Haigh says that in two years of that kind of organic growth, Grosvenor has covered 12% of its London estate with green lease clauses.
What about suppliers?
Supplier emissions accounted for 61% of the company’s total in 2021. These figures are largely based on estimates: only 10% of suppliers report their emissions to Grosvenor. What the developer – and many others – do is use a tool called Quantis that extrapolates a total based on global estimates.
The problem is that global estimates might not have any resemblance to a company’s actual suppliers. For example, Haigh says, Grosvenor’s cleaning contractor, Ethos, uses an electric fleet and low-chemical cleaning products. “We know that their impact is going to be a lot lower than a generic figure, but we didn’t have the data.”
With no simple alternative, companies turn to Quantis. “There’s that kind of herd mentality that if we’re all doing it, at least we’re all doing it wrong together,” says Haigh.
To bridge the data gap, Grosvenor has launched a supplier mentor programme with a charity called Heart of the City to help the companies they work with set their own science-based targets (SBT). More than a third of the developer’s contractors have signed up.
“We thought we’d have to do the hard sell, explaining why this is important,” Haigh says. But instead, there has been a lot of interest, and a greater uptake of the programme than Grosvenor expected.
He expects 35% of suppliers to report emissions by the end of the year. Additionally, any new contracts worth more than £1m will require an SBT from the supplier, which means Grosvenor will know what their emissions are.
Businesses signed up to the Science-Based Targets Initiative are expected to re-baseline their emissions every five years. That means by the time Grosvenor’s deadline comes up in 2025, it can adjust its targets based on actual data, rather than estimates. Haigh suggests the developer might even re-baseline earlier than that.
He says: “We really need to be as transparent as possible about getting real data, sharing it not just on our website so other people can see our results, but actually with our tenants, with our supply chain, because that’s how you move the dial.”