Author: Helen Wilkins / Editor: Charlotte Davies / Codes: SLO11 / Published: 30/06/2026
I first became involved in sustainability work three years ago when I became the sustainability lead for our Emergency Department (ED). Shortly afterwards I joined GreenED: the Royal College of Emergency Medicine (RCEM) initiative supporting emergency departments to reduce their environmental impact. In April, University Hospital Coventry received the Gold GreenED accreditation. We are only the second Trust in the UK to achieve this (after Northumbria Specialist Emergency Care Hospital) and the first Major Trauma Centre. We started our work during the pilot phase, I think in early 2022. We weren’t part of the original pilot but I got involved with GreenED during the end, by just going through the framework and working through the projects one by one.
Our trust formally signed up in 2024 by which time I could demonstrate many thousands of pounds of savings.
I also became part of ESIG in 2024 Sustainability – RCEM (the environmental specialist interest group for RCEM) and that has been instrumental in generating new ideas for projects and just generally meeting like-minded people to work with.
We did our bronze during the first formal accreditation cycle in late 2024 then silver in early 2025, gold in late 2025.
GreenED provides a framework of 36 evidence-based initiatives, divided into Bronze, Silver and Gold accreditation levels. Bronze actions focus on relatively straightforward changes such as improving recycling or reducing single-use plastics in catering, while Gold actions often involve organisation-wide policies such as climate adaptation planning for flooding or heatwaves, or “no-idling” policies for ambulances and other vehicles on site. An online portal provides implementation guidance, carbon calculators and data collection tools to quantify environmental impact and estimated cost savings. In the most recent accreditation round, 11 UK sites were recognised (1 Gold, 2 Silver and 8 Bronze), alongside 4 sites in Ireland and 10 in Australia with estimated annual projected savings of 131 tonnes of CO2e and projected estimated £216000 of annual cost savings. These figures likely underestimate the true impact as they include only projects with measurable evidence.
Leading sustainability work has provided valuable insight into how hospitals function beyond clinical care: from waste segregation processes to emerging technologies such as solar power and hydrogen-powered generators. One consistent observation is the amount of waste embedded within routine healthcare processes. Many of our projects have therefore focused on reducing unnecessary investigations and equipment use. In one audit we found that among patients under 40 years old, approximately 30% of blood tests requested were not indicated according to national guidance. Reducing unnecessary cannulation resulted in a 32% reduction, saving approximately £20,000 per year, plus reducing plastic waste. A simple audit of the ED storeroom and ordering lists also generated £35,000 in annual savings by removing unused or unnecessary items.
Targeting “carbon hotspots” can further increase impact. For example, switching from standard metered-dose inhalers to Salamol roughly halves the associated carbon footprint, while dry powder inhalers offer even greater reductions. Nitrous oxide (Entonox) is another major contributor to emissions: reducing its use, considering alternatives such as methoxyflurane (Penthrox), or switching off piped nitrous oxide manifolds can significantly reduce departmental emissions. More broadly, procurement accounts for around 75% of the NHS carbon footprint, highlighting the importance of reducing unnecessary purchasing and engaging with suppliers around sustainability.
Engaging staff during periods of operational pressure can be challenging. Framing sustainability initiatives around financial savings, workload reduction and improvements in patient care has helped maintain momentum, alongside practical demonstrations of waste (for example collecting a day’s worth of disposable tourniquets used in blood sampling). Green initiatives are also great quality improvement projects for resident doctors and advanced care practitioners with rapid results.
Some of the most notable achievements in Coventry included a 93% reduction in Entonox use, 50% reduction in unnecessary coagulation screens, introduction of reusable suture sets saving around 10,000 surgical instruments annually, and trust-wide crutch recycling saving around 40 pairs of crutches each month in the Emergency Department alone. As part of the gold accreditation, we looked at plant-based catering across the trust, introduced social prescribing, and maximised staff and patient use of the green spaces on our hospital site. RCEM estimated that our Gold-level initiatives alone delivered around £50,000 in annual savings and 90 tonnes of CO₂ reduction. This is similar to driving 225K miles or 9 times around the world!
Entonox in Detail: Reducing entonox use was multifactorial. First of all, we worked out that it was used for 2 things, joint manipulations and also as analgesia (some of our frequent attenders had it in their care plans). We introduced penthrox (methoxyfluorane) for joint manipulations, then as we rolled out training for that we did an awareness campaign around environmental impact and using alternative, more environmentally friendly analgesia.
Once we had demonstrated around a 75% reduction in usage, we removed all cylinders except the ones in children’s ED so that it was a more difficult option to use.
We went through all the high intensity user care plans, 5 had entonox in them. All of them were unnecessary (alternative analgesia would be more appropriate) and all care plans had actually expired so we just deleted them.
Coagulation Screen:
Unnecessary coagulation screens. When we started out the majority of patients attending ED majors were having a coag screen as part of their bloods taken ED. We changed it so that it was a rule in (so only meeting national guidelines). (see poster)
We laminated a card with the indications for coag screens and put it over the bottles in the blood taking trolley (see image). This intervention plus an education campaign for both nurses and doctors reduced our number of coag screens performed by around 50% which was a huge saving!
The sign-up fee for GreenED is £2000 per year, which supports RCEM in running the programme and managing the accreditation process. The fee originally was closer to £1000 so not too bad. I actually had no issue at all in getting the trust to pay as I was able to demonstrate a breakdown of the significant financial savings we have made with various green projects. Scottish, Welsh and Republic of Ireland governments are supporting sites to undertake the GreenED so the cost doesn’t come from the departmental budget.
RCEM captured around £50k of savings for both our silver and gold award and I think bronze would have been similar. As mentioned in the blog these potential savings are likely to be a huge underestimate but RCEM were strict about what could be counted (quite reasonably!). My other advice to other sites would therefore be – tot up your savings before asking for the money. Joining greenED will save money overall but the managers will need to be persuaded!
In practice, this cost is quickly offset by the financial savings generated through sustainability initiatives. One of the most positive aspects of participating in GreenED has been the collaboration between emergency departments. Monthly online meetings allow participating sites to share ideas, discuss progress and troubleshoot challenges, creating a supportive network for departments working towards accreditation.
The NHS accounts for approximately 4% of England’s total carbon footprint. Programmes such as GreenED demonstrate that improving sustainability in emergency care is not only achievable, but can also reduce costs, improve efficiency and support better patient care. For departments interested in getting involved or learning more about the programme, further information is available via the GreenED website and our RCEMLearning blogs:
One Response
good update