Can 100% of a city’s electricity come from renewables?

Cities around the world are increasingly shifting to renewable electricity. More than 80 UK towns and cities have now committed to switching to 100% clean energy by 2050, it was announced last month by the UK100 network of local government leaders. This includes major cities, Manchester, Birmingham, Newcastle and Glasgow, and 16 London boroughs.

Momentum is growing in the US too: 58 cities and towns have now committed to transition to 100% clean, renewable energy, including the big cities of Atlanta and San Diego. Earlier this month, the US municipalities of Denton, Texas, and St. Louis Park, Minnesota, became the latest communities to establish 100% renewable energy targets.

This is a hugely important trend given that cities are responsible for 70% of energy-related CO2 emissions. As the Intergovernmental Panel on Climate Change (IPCC) meets in Edmonton this month to discuss the role of cities in tackling climate change, it’s clear cities are critical to the Paris Agreement. As Director of Cities at global environmental impact non-profit CDP, I believe there is immense potential for cities to lead on building a sustainable economy.

Reassuringly, our data shows much commitment and ambition. Cities not only want to shift to renewable energy but, most importantly, they can.

At CDP we currently hold information from more than 570 of the world's cities, 100 states and regions, and 6,300 companies. They all voluntarily disclose their environmental impacts and actions through our annual questionnaire. Through this disclosure and insight, CDP aims to drive cities, companies and governments to take action to reduce their greenhouse gas emissions, safeguard water resources and protect forests.

Our data also shows more than 40 cities are already sourcing 100% of their electricity from renewables. These include Burlington in the US, Basel in Switzerland and Iceland’s capital Reykjavik.

They demonstrate that 100% renewable electricity is possible today. But what’s stopping other cities from getting there and how can those challenges be overcome?

In our latest data release The World’s Renewable Energy Cities, 100 cities now report that they source at least 70% of their city-wide electricity from renewables such as hydropower, geothermal, solar and wind. The list includes large urban centres such as Auckland, Nairobi, Oslo, Seattle and Vancouver.

The data comes from an extensive questionnaire sent to cities each year, with more than 570 responding in 2017. The data in this map comes from responses to the question “please indicate the energy mix of your electricity consumed at the city-wide scale” with cities entering a percentage next to each source.

For example, Vancouver gets 98% of its electricity from renewable sources – mostly hydro with some wind and biomass – and just 2% from gas. The city is currently investing in decentralized, neighbourhood-scale renewable energy projects.

Meanwhile, Auckland is sourcing 80% of its electricity from renewables, mainly from hydro, geothermal and wind. In this case, national leadership is playing an essential role. Auckland Council's chief sustainability officer, John Mauro, said the city’s energy mix is typical of the national grid. The national government is stepping up its ambition by replacing New Zealand's target of 90% renewable electricity by 2025 with an aspirational drive for 100% along with a new Zero Carbon Bill.

1. Economic

In 2017, unsubsidized renewables were already more cost effective than fossil fuels in 30 countries. The costs continue to plummet with the International Renewable Energy Agency (IRENA) projecting that energy from renewables will be cheaper than fossil fuels worldwide by 2020. As such, the economic barriers to the deployment of renewable energy are fast being overcome.

Within this context, investing in renewable energy makes increasing economic sense and cities are responding to this new market reality – as well as, of course, the new reality of climate risk.

According to our data, the 570 cities reporting to CDP are currently instigating renewable energy developments valued at $2.3 billion across nearly 150 projects. This forms part of a wider shift by cities to develop 1,000 clean infrastructure projects, such as electric transport and energy efficiency, worth more than $52 billion.

2. Technological

Being a “renewable electricity city” means producing or procuring enough clean electricity to cover a city’s needs.

Cities often don’t have control over the utilities in their region, so one clear challenge is working with them to procure renewable energy. For example, in Vancouver, the city is tied into using the provincial energy utility. The good news is that the utility provides 93-97% renewable power. But it does mean the city cannot easily shift those last few percentage points, especially as the utility’s power is extremely cost-effective. In the longer term, they are looking to install more renewable energy capacity at the residential and district scales.

Alternatively, some cities, such as Basel and Burlington, have chosen to set up their own city-owned energy companies, to have greater control over their city’s energy. Where politically feasible, this can be an effective option.

Given the location-specific and variable nature of renewable energy technologies, energy storage can also be a significant challenge. But as technological advancement continues apace, this is becoming easier to deal with. Auckland’s Mauro says technological breakthroughs are enabling increasingly localized renewable energy, through storage, district systems and smart grids, which means New Zealand’s ambitious national target is achievable, as long as the right policy frameworks and incentives are in place.

3. Political

A lack of political leadership can be a significant barrier to progress on renewable energy. The city of Basel, which transitioned to 100% renewable electricity, underlines this as crucial to their success. Basel told CDP that a clear and compelling vision is needed to engage citizens and other stakeholders.

It is vital to focus on the full 360-degree benefits of renewable energy, such as clean air, energy security, job creation and attracting new business.

Vancouver offers a strong business case for renewable energy. The city has an ambitious action plan to become the world’s greenest city by 2020, which includes boosting green jobs and environmental action from their business community. Their strategy is having clear economic benefits. Since 2010, they have seen a 47% increase in green jobs. These are not all in the clean energy sector, as it includes other areas such as local food production, but clean energy is a key part of their economic strategy.

The primary action for cities is to understand their energy mix and overall environmental impact. Once cities have this knowledge and insight, they can make a commitment to transition to renewable energy and develop an action plan based on ambitious targets. If action is going to take place, it’s crucial to have a clear vision towards which they can work.

Finally, cities must engage with large energy users to aggregate demand for renewable energy and encourage their utility to increase renewable energy supply as advocated by the report Pathways to 100.

We are seeing fast progress on the economic and technical aspects of the energy transition. Now, to tip the balance, we need a fundamental shift that makes renewable energy a political imperative. As the epicentre of social and economic progress, cities can and are leading the way to our low-carbon future.

Encouragingly, our 2017 data highlights how cities are stepping up action on climate change, with a sharp rise in environmental reporting, emissions reduction targets and climate action plans since 2015. But more must be done and we urge all cities to report through our new platform during May and June of 2018.