A Review of Decarbonisation Standards For Buildings

Executive Summary & SSE Recommendation

Selecting one of the many building standards, such as BREEAM or NABERS alone, does not guarantee either decarbonisation or compliance with requirements such as Building Regulations or ESOS. SSE recommends the adoption of ISO 50001, ideally externally certified, and the inclusion of ISO 52120 as part of the documented process. In addition to working towards Net Zero, it will help to reduce energy costs as well.

Introduction

Energy Sustainability Managers (ESMs) are increasingly being employed, like SHE and Quality Managers, to provide an independent assessment of an organisation's performance in these areas and a mechanism for reporting these unbiased audits to Senior Management. As net zero and decarbonisation measures are increasingly being scrutinised by shareholders and during M&A discussions, a robust decarbonisation strategy, independently audited, can affect the value and direction of such negotiations. To conduct their work and to provide an independent framework for external auditors, it is considered best practice to adopt an internationally recognised Standard for decarbonising buildings.

Building Standards

Standards such as BREEAM, LEEDS, NABERS, and the like have been developed over time by different organisations with different aims and objectives. The most recent, a pilot Standard called the UK Net Carbon Building Standard, was released on 22nd September 2024 and so its impact has yet to be seen.

There are different advantages and disadvantages to each, and Appendix I describes these. The main perceived disadvantages of such Standards are an increase in the initial cost of a building, and the potential to use them as “box-ticking” or “greenwashing” exercises rather than an actual attempt to decarbonise.

ISO Standards

A longer-term and more effective approach, that is becoming increasingly popular, is the adoption of international ISO Standards that place an emphasis on audited continual improvement. Just as ISO 9001 requires an organisation to make continual quality improvements, so there is ISO50001, which improves energy use and decarbonisation. This makes it easy to integrate energy management into other efforts, such as quality and SHE.

ISO 50001 Energy Management

This is an international standard for energy management systems (EnMS). It provides organisations with a framework to manage and improve their energy performance, including energy efficiency, energy use, and consumption. Many organisations and their shareholders have recognised that this Standard offers the best path to achieving and maintaining Net Zero.

Key Features

1 Systematic Energy Management

Provides a structured approach for organisations to integrate energy efficiency into their overall management practice.

2 Energy Performance Improvement

Helps organisations identify opportunities to reduce energy consumption and improve energy efficiency continuously.

3 Plan-Do-Check-Act Cycle

The standard follows the PDCA approach.

3.1 Plan: Establish an energy policy, objectives, targets, and action plans.

3.2 Do: Implement the energy management plans.

3.3 Check: Monitor and measure results, including energy performance and the effectiveness of the EnMS.

3.4 Act: Take actions to improve energy performance continuously.

Although it is possible to self-certificate, there is evidence that certification by external bodies increase energy and carbon savings by 60% ISO 50001 is scalable to any size of organisation and is supported by a number of other ISO standards (See Appendix II)

Of these, the most important is ISO 52120 Energy performance of buildings — Contribution of building automation, controls and building management. ISO 52120

ISO 52120

,This Standard is specifically designed to review BMS performance and strategy, and the influence it has on a building’s energy consumption by comparing a building's BMS against the best practices as described in the Standard. It was created by the European (CEN TC 247) committee and has been independently verified by the Technical University of Dresden. Like the energy efficiency rating on your refrigerator, this standard divides BMS systems into efficiency classes, in this case from A to D.

Energy efficiency Class C is the baseline for buildings with a BMS. Buildings in which the BMS is not operating efficiently, or buildings without BMS, are rated as Class D and typically use 50% more energy than those with a Class C rating.

Extensive research has shown that moving from a simple time-based strategy (Class C) to a demand-led (Class A) strategy can result in significant energy and carbon reduction, depending on the building type. Applying ISO 52120 as part of the overall strategy of ISO 50001 offers the best route for decarbonisation. This combined Standards approach has other advantages.

Energy Saving Opportunity Scheme (ESOS)

Administered by The Environment Agency, ESOS is a mandatory assessment of UK organisations that meet the qualification criteria:

• Employs 250 or more people, or
• Has an annual turnover of over £44m and an annual balance sheet total in excess of £38m, or
• Is an overseas company with a UK-registered establishment which has 250 or more UK employees (paying income tax in the UK)

Organisations that qualify for ESOS must carry out ESOS assessments every 4 years. These assessments are audits of the energy used by their buildings, industrial processes and transport. The assessment must be carried out by external accredited auditors. The ESOS audit is designed to identify tailored and cost-effective measures to allow participating businesses to save energy and achieve carbon and cost savings. The audit costs are estimated to be significantly outweighed by the savings from implementing the recommendations.

However, it is an expensive and time-consuming process. Moreover, it is seen by many organisations as a box-ticking exercise because, whilst ESOS reporting is mandatory for qualifying organisations, the implementation of the energy-saving measures is not!

Adoption of the ISO 50001 standard means that almost all of the information required by the auditor is already available, reducing the burden on both the organisation and the auditor.

Building Regulations Part L

Building Regulations Part L is a section of the UK Building Regulations focused on the conservation of fuel and power. It sets standards for the energy performance of buildings to improve energy efficiency and reduce carbon emissions. Part L2 specifically focuses on the conservation of fuel and power in buildings other than dwellings. It is subdivided into two further parts, Part L2A sets the standard for new buildings whilst Part L2B sets the standard for existing buildings.

ISO 52120 controls ratings are specifically referred to in the Regulations, and specify that…

This is the baseline position for a building with a BMS, so not particularly challenging. However, in the specification for a building automation and control system, the Regulations state…

The Regulations further go on to state that…

So, whilst currently falling short of specifying compliance with this standard as a requirement, a Class A rating would demonstrate compliance with these Regulations.

Conclusion

Selecting one of the many building standards, such as BREEAM or NABERS alone, does not guarantee either decarbonisation or compliance with requirements such as Building Regulations or ESOS.

Of far greater benefit to organisations is the adoption of ISO 50001, ideally externally certified, and the inclusion of ISO 52120 as part of the documented process.

In addition to working towards Net Zero, it will help to reduce energy costs as well.