‘Adopting renewable energy in cities could reduce consumption by 50%’
A TRANSITION to modern district energy systems could contribute to 60 per cent of required energy sector emissions reductions by 2050, and reduce primary energy consumption by up to 50 per cent, according to a new report launched at the weekend by the United Nations Environment Programme (UNEP) in collaboration with the Copenhagen Centre on Energy Efficiency (C2E2), ICLEI – Local Governments for Sustainability, and UN-Habitat.
With cities accounting for 70 per cent of global energy use and for 40-50 per cent of greenhouse gas emissions worldwide, District Energy in Cities: Unlocking the Potential of Energy Efficiency and Renewable Energy, reveals how local authorities and national governments can develop energy-efficient, climate-resilient and affordable district energy systems as one of the most cost-effective and efficient solutions for reducing greenhouse gas emissions and primary energy demand, and for helping to keep global temperature rise to two degrees Celsius above pre-industrial levels.
District energy systems can also contribute to the green economy transition through cost savings from avoided or deferred investment in power-generation infrastructure and peak capacity; wealth creation through reduced fossil fuel expenditure, local tax revenue; and employment.
“Our response and our ability to keep the world within a 2°C scenario, has led us to focus on district energy in cities. These are practical, reliable, bring benefits to consumers and they generate benefits in terms of our response to climate change,” said Achim Steiner, United Nations Under-Secretary-General and Executive Director of UNEP.
“In launching this report, we want to draw attention of the world’s decision makers, mayors, leaders at the community level, to the importance of district energy systems and hopefully through the lessons learnt in many parts of the world, ensure that this is yet one more element of our response that will allow us to practice and draw upon solutions already in place, proven and part of the transition to a green economy.”
Currently, heating and cooling, of space and water, account for half of the energy consumption in some cities, with systemic inefficiencies incurring massive economic and social costs, and acting as a major barrier to universal access to modern energy.
Cooling demand in particular is growing worldwide, spending on energy services is increasing. According to the International Energy Agency, energy consumption for space cooling increased 60 per cent globally from 2000 to 2010, and is set to expand by 625 per cent by 2050 in selected regions of Asia and Latin America.
District energy systems – which pipe steam, hot water or cold water around a city from a central location for use in buildings – are being used in a variety of cities worldwide because of their higher energy efficiency which can significantly reduce the greenhouse gas emissions of cooling and heating. This can result in improved air quality, and, where district systems use renewable power sources, reduce reliance on fossil fuels and energy imports, increasing the resilience of cities to fuel price shocks.
The city of St Paul, Minnesota, USA, for example, uses district energy fuelled by municipal wood waste to displace 275,000 tons of coal annually and to keep US$12 million in energy expenses circulating in the local economy. And in Toronto, Canada, the extraction of lake water for district cooling reduces electricity use for cooling by 90 per cent, earning the city US$89 million from selling a 43 per cent share in its district energy systems, which it could use to fund other sustainable infrastructure development. Paris, France, is providing cheaper, more renewable heat through district heating and, by owning a third of its district heating company, also benefits from an annual dividend of $US 2.6 million and an annual concession fee of $US 9.1 million.