Earth Day 2025: 8 challenges that support Our Power, Our Planet
This Earth Day, we’re reflecting on the theme Our Power, Our Planet – a global call to action reminding us that we each hold the power to protect our planet.
At Challenge Works, we’re proud to harness that power through innovation, collaboration, and impact-led design. Through challenge prizes, we have helped unlock bold solutions that drive sustainable energy, improve efficiency, and inspire change – and we’ll continue to.
In celebration of Earth Day 2025, here are eight of our challenges – past, present, and potential – that bring this year’s theme to life.
1. Manchester Prize Round 2: Clean Energy Systems
Current challenge, delivered for the UK Government’s Department of Science, Innovation and Technology
The Manchester Prize is a multi-million pound, multi-year challenge prize, launched in 2023 and funded by the Department of Science, Innovation and Technology to reward UK-led breakthroughs in artificial intelligence for public good. Round 1 has now closed and winners were announced in May 2024.
Round 2 is focusing on cutting-edge AI solutions that can accelerate the UK’s shift to clean, secure energy. From optimising energy use to scaling clean technologies, the prize will support UK-based innovators whose AI breakthroughs reduce energy demand and improve the efficiency of our energy systems. With £100,000 in seed funding and up to £60,000 in compute support for each finalist — and a £1 million grand prize — this challenge is backing AI for public good, and for the planet.
2. Renewable Energy Challenge
Past challenge, delivered for the Mayor of London
The Renewable Energy Challenge was part of the Mayor of London’s Mayor’s Resilience Fund, funded by the London Economic Action Partnership. The fund supported innovation in response to pressing urban challenges and was rolled out in two phases: an open call in 2020 for local authorities, charities, and public agencies to come forward as problem-holders, followed by the design and delivery of ten city-focused innovation challenges in 2021.
This particular challenge focused on harnessing the potential of the Royal Docks water area to develop a proof of concept for renewable energy production. The aim was to create a scalable, transferable, and commercially viable prototype that could deliver clean energy to local customers, including businesses, landlords, developers, residents, and infrastructure projects. The challenge area included the Royal Victoria, Royal Albert, and King George V Docks.
The desired outcomes included the development and real-world testing of a physical renewable energy prototype capable of delivering power to the local grid or directly to users. In the longer term, the challenge sought to stimulate significant renewable energy production in the Royal Docks and create a blueprint that could be replicated in other water-based urban locations.
The winning solution, announced in 2022, was Royal Docks Floating Solar by Renewable Connections Developments Limited – a floating solar array designed to generate clean electricity for London City Airport and other nearby consumers, marking a major step forward for sustainable urban energy.
3. Energy and Environment Open Data Challenge
Past challenge, funded by Innovate UK and the UK Government’s Department for Business, Energy and Industrial Strategy (BEIS)
The Energy and Environment Open Data Challenge was one of seven challenges in the Open Data Challenge Prize Series created to inspire innovative, open data-driven solutions to pressing societal issues. The challenge encouraged participants to develop tools and services that would enable communities to group-buy energy, implement energy efficiency interventions, or begin generating their own power. The initiative aimed to bridge the gap between the UK’s leadership in open data publication and the limited real-world application of this data, especially by innovative start-ups and SMEs.
The winning solution was Community Energy Manager (CEM), a platform designed to empower community energy groups by simplifying complex processes, sharing best practices, and leveraging key open datasets. Its expected social and environmental impact included more efficient homes and reduced emissions, while early economic evaluations by PwC projected significant returns, including up to £32.1 million in social impact and up to £5.6 million in environmental benefits within three years.
4. Dynamic Demand Challenge
Past challenge, delivered in partnership with the National Physical Laboratory’s Centre for Carbon Measurement (NPL)
This £100,000 prize was designed to stimulate new products, technologies or services using data to achieve reduced carbon emissions by shifting energy demand to off-peak times or through excess renewable generation. It was delivered in 2014 to stimulate demand side response solutions for households and small businesses. At the time, electricity generation accounted for around 30 per cent of UK CO2 emissions, with the primary source of UK electricity still predominantly fossil fuels. Pressure on and from governments to move towards a low-carbon economy added ongoing complexity to this problem through increased use of decentralised renewable energy generation.
An important barrier to the use of renewable energy is that its intermittence means it may need to be matched with other non–renewable sources of energy that provide base load for power grids. Dynamic demand, or demand–side response (DSR) is the exchange of information between electronic devices, responding to signals from the grid directly or indirectly. These products or technologies can help shift electricity consumption away from peak hours where electricity consumption is high, or enable greater usage of excess electricity generation from renewables, as well as help maximise the use of a smart infrastructure.
5. UNDP Renewable Energy Prize
Past challenge, funded by the United Nations Development Programme (UNDP)
Launched in 2012 by the United Nations Development Programme in Bosnia and Herzegovina, this challenge sought to find a sustainable, off-grid renewable energy solution for returnee families in remote rural areas.
The aim was to design and develop a sustainable, cost-effective solution for a standalone, off-grid renewable energy supply that could deliver 1.25 kWh of electricity and 120 litres of hot water daily, meeting the basic needs of a typical household, that would not cost more than €5,000. This initiative responded to the long-standing issue of over 3,000 families still living without electricity after returning home post-war, where extending the national grid was no longer economically feasible.
The prize received 35 entries. After two months of field testing the system installed on Zoran Rodić’s housing unit in Veliko Ocijevo, Drvar, was named the winner. The system received a US$20,000 cash prize. The chosen solution not only met but exceeded technical expectations and was successfully piloted with up to 50 families.
6. Step-up Energy Access Challenge
Potential future challenge
This £10 million challenge would seek inclusive, low-carbon energy solutions that empower communities in low- and middle-income countries to climb the energy ladder – from basic access to reliable, affordable electricity that supports local economic growth.
Despite global progress, 759 million people still live without electricity, and many more experience unreliable access. The challenge would call for decentralised, renewable energy systems that are resilient, repairable, and tailored to local needs, serving households, businesses, and essential services at an accessible price point.
To foster innovation and inclusion, ten diverse city or regional testbeds would be selected, ranging from rural off-grid areas to informal urban settlements. Special outreach efforts will target local, underrepresented groups, including women and youth.
Unlike traditional funding, this prize model offers startups the flexibility to trial scalable, purpose-driven models without the pressure of immediate returns, helping to close the finance gap in low-income energy markets.
7. The Unleashing Energy Prize
Potential future challenge
The Unleashing Energy Prize would aim to accelerate the UK’s transition to net zero by addressing key barriers in the energy sector, particularly the lack of grid capacity and the inflexibility of renewable energy sources. The challenge would focus on overcoming two major issues: delays in grid connections due to insufficient infrastructure, and the unpredictability of renewable energy sources like wind and solar, which can lead to wasted energy.
The prize would encourage innovators to develop solutions that either:
- Decarbonise industrial heat without adding new grid connections, focusing on technologies like autonomous renewable energy generation, thermal storage, and heat pumps.
- Harness intermittent renewable supply to power energy-intensive processes, such as recycling or creating green hydrogen, or integrate storage into domestic appliances.
The challenge model would drive technological innovation, reduce costs, and stimulate fresh approaches to decarbonisation, with a final prize awarded to the team that demonstrates the most cost-effective decarbonisation solution. This approach supports multiple types of solutions, from thermal storage to industrial heat and domestic systems, and could help unlock a faster transition to a net zero energy system.
8. Home energy efficiency prize
Potential future challenge
This is a prize that would reward clever solutions that achieve small gains in homes’ energy efficiency.
The UK’s built environment is dominated by old buildings that weren’t designed for energy efficiency. Victorian terraced houses with wobbly sash windows. Sixties blocks with paper-thin walls. Edwardians built homes with huge steel beams to hold up the ceilings – they do a terrific job at holding the roof up, but they’re also remarkably good at conducting the cold in the middle of winter.
We all know there are big things we can do – get loft insulation, replace windows, or get a heat pump. But the energy inefficiency of our housing stock is also down to a thousand and one tiny problems – uncapped chimneys, air bricks that leak heat, poorly-designed heating systems. If we fixed all these small problems, the marginal gains could add up to a big difference.
There must be hundreds of clever solutions for all the tiny niggles our houses have. So let’s celebrate these marginal gains! We want to offer a £1m prize for the best ideas for how to plug these gaps in our houses’ energy efficiency – there’s potential for a huge range of solutions, from cutting heat loss, making lighting more efficient, to managing electricity use and more. And it makes sense as a prize because, despite this huge variety of solutions, they could all be judged on the same clear metric: on energy saved, ease of use, cost and size of market.
We believe in the power of people to shape a better, greener future.
Through our challenges, we aim to unlock bold ideas that bring about real environmental and social change – and we’re just getting started.
The best prize ideas are developed through extensive research and engagement with experts, stakeholders and people with lived experience of the problems they are focused on. We start with a first draft and then work to improve, refine and validate our thinking.
We’re particularly keen to have conversations about ideas with potential funders and organisations working in the field. Get in touch if you’re interested and we’ll schedule a call.
