Future of Cities: Urban Regeneration in a Time of Crisis
An Interview with ROCKWOOL Group’s Mirella A. Vitale
Cities and urban areas are increasingly finding themselves on the frontlines of the global climate crisis — both as emitters of damaging greenhouse gases and in terms of their vulnerabilities to the effects of climate change. According to available statistics, buildings alone account for around one-third of global energy consumption and 20% of CO2 emissions — a number that increases to 50% in major cities. Against that backdrop and as the world’s cities continue to grow with more than two-thirds of the world’s population expected to live in urban centers by 2050, the role of cities in combatting the climate crisis has never been more relevant.
The good news is that cities are already taking action through innovative solutions — from the creation of carbon-free zones and pushing green housing policies to managing waste and water sustainably and efficiently.
So, how are urban planners, architects and others working in the urban regeneration space to tackle the climate burden posed by cities? What role does innovation play in ensuring that cities are a victorious battleground in the fight against climate change? And what sustainable solutions have cities like New York already deployed in order to mitigate the effects of a warming planet?
Denmark in New York caught up with Mirella A. Vitale, Senior Vice President of Marketing, Communication and Public Affairs at ROCKWOOL Group, to discuss how the future of our climate rests on the sustainable solutions we deliver to cities across the planet.
Denmark in New York: Thank you, Mirella, for joining us in this inaugural Future of Cities interview. We know that cities hold the key to reducing global carbon emissions. What are some of the strategies that architects and builders should adopt to ensure that buildings are no longer leading polluters of our planet’s urban areas?
Mirella A. Vitale: Buildings account for an incredible 30 percent of the world’s CO2 emissions and energy consumption, with pollution generated through heating and lighting, water supply and air conditioning, and during the construction of the building itself. With the environmental impact of buildings currently so high, it is crucial that builders and architects look creatively at ways to reduce buildings’ carbon footprint and tackle climate change.
Energy efficiency renovation is the main way that buildings can be made greener. Architects can look to “Nearly Zero energy homes” and other aspirational energy efficiency standards for a range of upgrade options. In practice, this means reducing the need for heating by installing technical thermal insulation and upgrading windows to modern glazing standards. It calls for low-energy LED lighting, thermal pumps that take advantage of heated groundwater, and design techniques that make the building airtight, ensure a comfortable and healthy indoor environment and reduce loss of heat.
Deploying these techniques to upgrade buildings can have a major impact on emissions. In fact, worldwide, building renovation provides the most cost-effective method to reduce emissions when compared to other routes such as solar energy or fuel-efficient vehicles, with a €-150 marginal cost per ton of CO2 emissions. Across the board, saving one kilowatt hour of energy through stone wool insulation results in 480 and 220 times less carbon emissions than generating that same kilowatt hour from coal and gas respectively.
What are some tangible and innovative examples of how urban planners, architects and others are working in the urban regeneration space to tackle the climate burden posed by cities?
Mirella A. Vitale: There are some fantastic examples of cities innovating and undertaking regeneration projects that are having a major impact on the climate. Transport in urban areas has historically been a huge issue, with one third of greenhouse gas emissions from the C40 group of large cities coming from transport and traffic. Mayors in the 96 cities that make up the C40 have committed to procuring only zero-emission buses from 2025; and set a policy that means a ‘major area’ of their cities will be zero emission by 2030. This will include charges for driving high-polluting vehicles in cities, and the rollout of charging points to encourage the use of electric cars. Some are taking the drop in traffic since COVID-19 as an opportunity to make significant progress, with London now redesigning the roads of its central business district cycle and pedestrian only.
There are also cities that are planning ambitious renovation of public buildings to reduce emissions. During a research programme piloted in New York City, deep retrofits of 23 high-emission public schools were shown to reduce greenhouse gas emissions by 42 percent. An even more ambitious programme remediating 700 schools across the city would avert 318,690 tonnes of CO2 per year, equal to 9.56 mega tonnes of CO2 across the buildings’ lifetime with energy cost savings of $99 million per year.
Where energy is used, it should be the greenest energy source possible, and where cities can integrate wind turbines and solar panels into design that will further contribute toward a resilient and healthy urban environment.
Across all major cities, we are seeing a drive to open up more green space, both for environmental reasons and to improve the wellbeing of those who live in cities. In some cases this is incredibly creative, and New York’s Highline project is one of my favourite examples of how old brownfield space is being reclaimed as parks and gardens.
What sustainable solutions has ROCKWOOL already deployed in order to mitigate the effects of a warming planet?
Mirella A. Vitale: ROCKWOOL is the world’s leader in producing stone wool insulation, which we originally developed as thermal insulation for buildings. This remains its primary purpose, and in 2019 we sold building insulation products that in their lifetime will save globally the equivalent of the annual carbon emissions of Denmark, Norway and Sweden together. That is 888 terawatt-hours of heating energy, 200 million tonnes of carbon dioxide, equivalent to 100 times the carbon emitted in the production of our stone wool.
However, we have also developed a range of other applications for stone wool. For example, it can be used in hydroponics, replacing soil and enabling modern horticulture to increase production while using fewer natural resources. Relative to growing in soil-based systems, Grodan products sold in 2019 resulted in an estimated 100 million litres less water used, and saved nearly 30,000 hectares of land, an area more than three times the size of Paris. Hydroponic horticulture and urban farming are exceptionally exciting new areas, and is likely to play a significant role in feeding future cities and achieving healthy and sustainable diets for all.
Our products can also be used to mitigate urban flooding, a risk that has been made far worse through global warming and unpredictable weather patterns. Our Rockflow system sees a buffer of specially engineered stone wool installed underground with connections to a system of pipes, drains and gullies. As it rains, the water is quickly absorbed and then gradually discharged into the surrounding soil or sewer system. The stone wool in the Rockflow system can absorb 95 percent of its volume in water, helping to significantly reduce surface flooding.
What key actions can cities take in order to ensure a healthy and resilient urban environment, while preserving existing buildings?
Mirella A. Vitale: Upgrading our urban environment does not mean having to remove old buildings and starting again. Nor would this be desirable. Buildings make a city unique, with architecture forming a vital part of cultural heritage. What is important is to upgrade this existing building stock so that it is safer, more thermally efficient and requires far less energy to power them.
Where energy is used, it should be the greenest energy source possible, and where cities can integrate wind turbines and solar panels into design that will further contribute toward a resilient and healthy urban environment.
Emilie Haaber Lynggaard is the Strategic Communications and Press intern at Denmark In New York.
