UN advocates passive house in latest carbon emissions report
Prof Diana Ürge-Vorsatz

UN advocates passive house in latest carbon emissions report

Report author Prof Diana Ürge-Vorsatz praises “fantastic” Dún Laoghaire-Rathdown passive house policy

This article was originally published in issue 19 of Passive House Plus magazine. Want immediate access to all back issues and exclusive extra content? Click here to subscribe for as little as €10, or click here to receive the next issue free of charge

The influential Emissions Gap Report, published by the UN Environment Program each year to track the progress of governments on reducing their carbon emissions, has for the first time advocated for the passive house standard in its 2016 edition.

Chapter five of the report, which focuses on energy efficiency, includes a dedicated section on the passive house standard. It reads: “The standard has become popular in several countries, and is experiencing a dynamic market adoption in several regions. The global floor area of Passivhauses has grown from 10 million sqm in 2010 to 46 million sqm in 2016, with the most activity occurring in Europe.”

It continues: “Presently, the price premium for new Passivhauses in several countries is comparable to standard construction costs.” The report also advocates for net zero energy and energy positive buildings.

Passive House Plus spoke to Prof Diana Ürge-Vorsatz, one of the lead authors of the chapter on energy efficiency, following the publication of the report. “We have a dedicated section on passive house, which is really quite a breakthrough, because usually the report is very short and doesn’t go into detail,” she said.

Professor Ürge-Vorsatz was also one of two co-ordinating lead authors of the chapter on mitigating emissions from buildings in the Intergovernmental Panel on Climate Change’s fifth assessment report, which was published in 2013, and also explicitly advocated for the passive house standard.

She said one reason the IPCC placed such emphasis on the standard is because of the inherent resilience of passive buildings.

“Once you have built it, it’s low tech,” she said. Building to the passive house standard was “not the ultimate goal”, she added, but “a very important intermediate goal” on the road to a built environment that produces more energy than it consumes. “The two have to go hand-in-hand — drastic demand reduction, and renewables.”

Prof Ürge-Vorsatz explained that while Assessment Report 5 offered many different scenarios under which global warming could be limited to 2C above pre-industrial levels, there would be much more flexibility in terms of the options available for society if energy efficiency was maximised first.

“The first goal is try to bring energy demand to as low as possible,” she said. “If you don’t work hard on your demand, you may have to do everything else.”

When Passive House Plus told Prof Ürge- Vorsatz about a comment Passive House Institute director Prof Wolfgang Feist made in these pages a few years ago — that the most ambitious action on climate change was coming from city governments and the European Union, rather than from national governments — she agreed. And like Prof Feist, she suggested this might be because anti-environmental lobbying is strongest at national level.

“Cities are becoming the powerhouse of action, more than national governments,” she said, describing the decision by Dún Laoghaire-Rathdown County Council in Dublin to make the passive house standard mandatory for new buildings as “fantastic”.

“There have also been a lot of progressive EU policies on climate change and the environment,” she added, describing the EU recast energy performance of buildings directive, which is mandating the nearly zero energy standard for all new buildings from 2021, as “extremely forward looking”.

But Prof Ürge-Vorsatz criticised retrofit schemes that only grant-aid basic energy upgrades like cavity wall and loft insulation, arguing that these ‘shallow’ retrofits don’t go far enough, and make it less likely that participating buildings will ever receive the deeper upgrades needed to drastically cut their carbon emissions. “I am fully convinced these initiatives are more detrimental than good. You really have to go for deep retrofits.”

She stressed that without the deep retrofit of our building stock, society would not be able to reach the 1.5C limit on global warming envisioned in the Paris Agreement without looking at more controversial options, such as major geo-engineering projects.

Prof Ürge-Vorsatz said it was not possible to rely solely on the market to deliver deep retrofits, because as she put it, “nobody invests in 20 year returns, especially when they are small scale.” She said that instead, government intervention and clever climate financing were both necessary to stimulate deep retrofit en masse.

Passive House Plus spoke to Prof Ürge- Vorsatz the day after Donald Trump had been elected US president, but despite the result, she was still relatively optimistic about the prospects for global climate action. She said the Paris Agreement on climate change had surpassed her expectation of how ambitious the global community could be in setting goals for tackling global warming.

She praised the climate expert community for embracing a new target of limiting global warming to 1.5C above pre-industrial levels, as envisioned in the Paris text.

“As compared to almost any expectation, it was really a miracle what happened in Paris,” she said. But she admitted to having deep concerns following the US election result. “Until yesterday morning I was very optimistic, now I’m much more worried.

“We have seen unprecedented, historic and miraculous improvements,” she said of global progress on climate change, “but it’s very fragile.”