Homes for bats, on-site allotments and recycled kits are just some of the ways Premier League clubs are continuing to improve their 'green' credentials.
Tottenham and Liverpool have come joint-top of the 2021 Green League - a table measuring the sustainability of all 20 top-flight sides.
Tottenham Hotspur players now travel to matches on coaches powered by biofuel, reducing squad coach travel emissions by over 80%. While other clubs such as Liverpool have committed to decarbonising fuel through the use of sustainable aviation fuel in the future, which would also reduce emissions by 80%.
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What is the sustainability table?
BBC Sport has worked with the United Nations-backed Sport Positive Summit since 2019 to research the sustainability of all 20 Premier League clubs, with the rankings updated each year.
Teams were asked to provide evidence of efforts in 11 categories. Two points are available for each category as well as two bonus points, making a maximum of 24 points.
Points were awarded for:
- Policy and commitment
- Clean energy
- Energy efficiency
- Sustainable transport
- Single-use plastic reduction or removal
- Waste management
- Water efficiency
- Plant-based or low-carbon food
- Communications and engagement
A bonus point was awarded if the club is certified to an internationally recognised sustainability management system or if a club track and report on percentage of fans taking various modes of transportation to games.
Liverpool CEO Billy Hogan said the club was "incredibly excited" with joint first place, adding: "The environment is incredibly important to the club and only becoming more so. I think probably like all organisations we're all concerned about the impact that we have on the environment and on our local communities.
On plans for more sustainable travel, Hogan said the club is looking to "balance the benefits" of flying to games "from a training and performance standpoint" with an issue that "people are particularly focused on" to reduce and offset the environmental impact.
Tottenham executive director Donna-Maria Cullen, said: "To have once again been named at the top of the Sport Positive League Table is fantastic recognition for the work that continues to be delivered across our organisation - now we must challenge ourselves to go further.
"Joining the UN Race to Zero is a significant next step on our journey and provides us with a clear pathway and emission reduction targets that we are prepared to meet."
What else are clubs doing to help?
The top two - Tottenham and Liverpool - both use players to engage via their own media channels and also in partnerships with other sustainable organisations.
Hogan said player involvement in Liverpool's sustainability work is important for the profile they have, adding: "Obviously, we're a relatively small organisation in terms of overall numbers of people, but we have an outsized impact in terms of the messaging that we can deliver on a global basis."
Arsenal have been offering their fans a special renewable energy tariff via green energy supplier, while Everton are working with fans to set up an 'Everton for Change' project group with six supporters helping to promote green initiatives to fellow fans and feed ideas back to the club.
There are three new categories introduced for the 2021 updates - biodiversity, education, and commitment & policy - with four clubs picking up points for committing to reduce emissions by 50% by 2030 and being net zero by 2040 via the high ambition track of UN Sports for Climate Action; Tottenham Hotspur, Liverpool, Southampton and Arsenal.
Manchester City has committed to an even more ambitious target of net zero by 2030.
Elsewhere, Liverpool have planted over 900 trees, hedges, bushes, and wildflower plugs at their Academy, as well as vegetables that the club chefs use. They also work with the local Hedgehog Society to protect the animals.
Similarly, Tottenham's Player Accommodation Lodge has built a barn and farmhouse to help house bats, as well as creating a wildlife corridor in an exclusion zone for guests.
All the clubs are working on the use of sustainable transport. Manchester City have a car-sharing scheme, with pricing advantages for multi-occupancy of cars, while Southampton's cycle to work scheme for staff comes with three free bike doctor sessions to ensure the bikes are safe.
Brighton are part of the 'On the Ball' campaign and provide complimentary, plastic-free sanitary products to fans and female players.
Food is another area that clubs are working on. Norwich use home-grown produce from their on-site allotment and have developed a Player Nutrition App which has extensive plant-based recipes.
A number of clubs are also tracking fan travel, with Spurs surveying fans after home matches. The club state they are close to achieving its target of no more than 23% of supporters (14,250 fans) travelling by private car on match days.
All the clubs encourage the use of public transport to their grounds.
"The power of sport within the climate crisis is the platform and influence it has to drive this change," Claire Poole, the CEO of Sport Positive Summit, said.
"We need staff, fans, players, suppliers, sponsors and citizens that clubs connect with, to receive training and education to understand the challenges we face, understand what their team is doing, and how they can take action."
Helping finances & the environment - Brentford's replica kit policy
Brentford announced in November that they would keep the same home kit for two seasons in a row.
The club did it to ease financial pressure on fans - full kits at some clubs can cost more than £100 - and also help the environment.
A shirt made from polyester - as most football shirts are - has more than double the carbon footprint of one made from cotton (5.5kg of carbon dioxide per shirt compared to 2.1kg).
Even recycled polyester takes hundreds of years to decompose and can lead to microfibres escaping into the environment.
"In terms of sustainability, this is a small step in the right direction," chief executive Jon Varney told BBC Sport.
"It has helped to get more people talking about what they can do to reduce waste, to recycle and to reuse things that we all own.
"This initiative grabbed the headlines but we know that we are at the early stages in our work to make the club more sustainable."
The Premier League became a signatory of the UN's Sport for Climate Action framework this season and chief executive Richard Masters told BBC Sport they are "continuing to work on our own strategy" on sustainability - looking for "alternative methods and practices" to help "reduce emissions and environmental impact".
"Clubs have demonstrated their commitment to positive change in this area and continue to play an important role in raising awareness of the issue among fans, while also working on policies to improve their environmental sustainability," said Masters.
What is the BBC doing?
The BBC is aiming to be net zero in terms of greenhouse gas emissions by 2030.
BBC Sport has signed up to the UN's Sports for Climate Action framework, making:
- a commitment to a 50% reduction in emissions by 2030,
- sustainable production training,
- a migration to remote working on Premier League football and major events, and sports journalism
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