Moving beyond compliance in the Energy Savings Opportunity Scheme (ESOS) 

The Energy Savings Opportunity Scheme (ESOS) is a mandatory programme requiring large UK businesses to review their energy use every four years and identify cost-effective energy efficiency opportunities across buildings, transport, and industrial processes. 



As Phase 4 begins, the spotlight is no longer solely on identifying opportunities—but on implementing them. 

One of the most significant developments in Phase 4 is the requirement to demonstrate progress against the commitments made in your ESOS Action Plan. This marks a decisive shift in the scheme’s intent—from reporting to delivery. 

Organisations are now expected to: 

• Show measurable progress towards implementing energy-saving opportunities identified in previous assessments. 
• Provide clear explanations where progress has not been made, demonstrating accountability. 

While the government has delayed the formal integration of Net Zero objectives until Phase 5, Phase 4 still encourages meaningful decarbonisation by ensuring that businesses follow through on their own energy efficiency plans. 

The real driver: project management and implementation

Although Net Zero is not a formal requirement in Phase 4, the direction of travel is clear. At Optimised, we believe ESOS should not be treated as a tick-box exercise. For businesses committed to sustainability, delivering on action plan commitments is a strategic opportunity to cut costs, reduce emissions, and future-proof operations. 

That’s why our focus is firmly on helping clients project manage and implement the opportunities they’ve already identified. It's not just about compliance—it’s about making change happen. 

Why this matters 

By shifting from assessment to action, Phase 4 introduces a higher level of scrutiny and responsibility. Businesses that embed energy efficiency into their operations now will be better positioned for future phases, especially as Net Zero requirements are phased in. 

Proactive implementation delivers benefits such as: 

• Lower energy bills through targeted efficiency upgrades 
• Stronger ESG credentials and progress towards climate goals 
• A smoother path to Phase 5 and beyond 

How Optimised can help

We provide expert support to help you turn plans into progress: 

• Project management for ESOS Action Plan implementation 
• Specialist energy and decarbonisation consultants 
• Compliance services tailored to your business needs 
• Verified savings and performance tracking 

Let’s make your ESOS Action Plan more than a report—let’s make it a roadmap to results. 

Book a free 30-minute consultation with our experts today and find out how we can help drive your energy efficiency projects forward.