Beyond MHHS: Why Forward-Looking Suppliers Should Consider a Future of Even More Granular Settlement

MHHS Is the Priority — But What Comes Next?

Market-wide Half-Hourly Settlement (MHHS), due to go live in September 2025, marks a major milestone for the UK energy sector. It will replace static profiling with 30-minute actual consumption data for all consumers—underpinning the path to such as dynamic pricing, more precise system balancing, and flexible energy systems.

For now, implementation and transition of MHHS is where focus belongs.

But energy leaders know market design doesn’t stand still. Advanced markets like continental Europe have moved to 15-minute settlement and Australia has already moved to 5-minute settlement. This offers more precise alignment between energy usage, generation, distributed energy resources and prices. It’s not something the UK will adopt overnight, or even in the near future —but in its decision on Zonal Pricing within REMA, more granular energy settlement has been called out by the UK government as a long term consideration.

“While 5-minute settlement may not be likely in the medium term, it’s our role to be ready. Just as we’ve helped retailers adapt to MHHS, we’re already aligning our technology roadmap to support future flexibility and faster market cycles.”
 Steve Roche,  Managing Director, ESG

The message isn’t that a 5-minute reform is coming tomorrow. It’s that the work you’re doing today for MHHS is part of a long-term market evolution that can either set you up for long-term adaptability or limit your options later.

What 5-Minute Settlement Represents

In a 5-minute market, energy supplier’s settlement positions within system balancing are six times faster than even the newly introduced half hourly settlement. That granularity demands:

• Finer price responsiveness and demand forecasting
• Accurate understanding of technology empowered consumer load shifting against both tariffs and flexibility opportunities
• Real-time customer propositions that align with the speed of Distributed Energy Resources, often far faster than even five minutes
• Real-time integration and operation of battery storage optimisation and automated demand response

While not yet on the UK’s regulatory near-term roadmap, the government’s considerations as part of REMA underpin an underlying trend toward speed, flexibility, and decentralisation.

Why This Matters (Even If Nothing Changes Soon)

1. Protect Current MHHS Investments

The real risk isn’t 5-minute reform. It’s building 30-minute systems that can’t scale or adapt. Most of the complexity in preparing for MHHS—data handling, platform design, billing logic—overlaps with what 5-minute settlement would require.

Future-proofing now avoids expensive rework later.

2. Build Optionality, Not Commitments

Nobody is recommending you implement 5-minute infrastructure today. But a few smart choices now—modular architectures, API-first platforms, scalable data pipelines—mean you’re ready if and when the landscape shifts.

3. Start Small with Low-Risk Steps

Energy leaders can explore time-aligned pricing, flexibility pilots, and real-time data models now—without regulatory pressure. These steps deliver immediate commercial insight and prepare teams and systems ahead of growing competition in distributed energy at scale.

Regulatory Context: A Distant but Directional Signal

DESNZ’s Review of Electricity Market Arrangements (REMA) has noted that shorter settlement windows couldincrease flexibility participation and reduce system costs. But there’s no active policy proposal, and no confirmed timetable.

ESG’s Approach: Designed for Later, Even If It’s Not Soon

At ESG, we support clients to meet today’s obligations—but also to make sure today’s systems don’t become tomorrow’s constraints.

“We believe it is appropriate to think ahead by aligning your tech roadmap to support what might come next – so you’re not boxed in by decisions made under pressure.”
Steve Veal, Billing Director ESG

Our platforms are engineered for:

• An adaptive architecture incorporating central system changes
• Dynamic product configuration
• Real-time system integration

We’re also engaging in:

• Smart tariff design
• Flexibility trials
• Long-term architecture reviews

Questions Worth Asking — Even Without Urgency

• Will our MHHS systems scale to more granular data if needed?
• Are we avoiding hardcoded logic that limits future options?
• Can we test time-of-use products now, without regulatory pressure?

Final Thought: Planning ≠ Overbuilding

No one’s calling for 5-minute compliance tomorrow. But long-term competitiveness depends on the choices made during MHHS preparation. Leaders who treat this as just a compliance project may find themselves constrained when the next wave of change does come.

If you’re reviewing your MHHS roadmap and want to ensure future readiness without over-investing today, ESG can help. Let’s talk about how.