ESOS software and ESOS online: what runs digitally, and what stays human

Four stages of ESOS digitise well, and a platform’s job is to make the two human stages shorter and cheaper.

The data stage pulls consumption from half-hourly meter feeds, bills, fuel cards and building systems into one dataset, in energy units rather than converted emissions.

The calculation stage adds up total energy across buildings, transport, industrial processes and any other purpose, as the Phase 4 guidance requires, and shows the areas of significant consumption that make up at least 95% of it.

The ESOS energy audit itself still needs a plan and site visits where consumption justifies them, and the finished ESOS assessment is reviewed by a lead assessor on an approved register unless an exemption applies.

The evidence stage assembles the records regulation 28 requires, which is where software saves most time.

The filing endpoint is official and free: MESOS, where the responsible undertaking submits the compliance notification by 5 December 2027.

Stages three and four are interleaved with the others, not appended at the end, which is why no platform runs an ESOS compliance period on its own.

ESOS software should be judged on its energy-data spine and its ESOS-shaped outputs, not on its dashboards.

The first test is the spine: can it ingest half-hourly data, bills and fuel cards on a schedule and keep an auditable trail from the raw feed to the reported figure?

The second is the outputs: total energy by purpose, coverage against the 95% floor where significant consumption is identified, an energy intensity ratio for each purpose, opportunities with kWh savings, and an evidence pack an assessor and the Environment Agency can follow.

The third is the assessor workflow: read access, query trails and sign-off records, because software that shortens the review shortens the critical path to the deadline.

The fourth is reuse: the same dataset should produce SECR every year, and where the group is listed, feed the Scope 1 and 2 figures for UK SRS S2.

The checklist beside this lists the ESOS and SECR outputs with their provisions; tick each one as a vendor shows it.

Of the seventeen vendors profiled on this site, only a few name ESOS on the pages we read, because ESOS is a UK-only scheme that global products rarely address.

Climatise describes an ESOS Phase 4 workspace from energy data to MESOS notification and the action plan, and sells it to the consultancies and lead assessors who deliver ESOS as well as to organisations that comply; its profile is on the Climatise page.

Watershed names ESOS among the UK reporting it works on.

Those are the vendors’ descriptions of their own products, not our assessment; put the requirement list to any vendor in writing and ask to see each output on your own data.

No vendor removes the lead assessor: consultancies and assessors are covered on ESOS consultants and assessors.

However complete the digital dataset, a lead assessor on an approved register must review the assessment under regulation 21, unless an exemption applies.

The approved registers are held by seven professional bodies, one of which is ISEP, and the GOV.UK ESOS page lists them all.

One or two responsible officers — board-level directors — confirm the assessment before notification.

ISO 50001 does not discharge the duty to carry out an assessment, and it never removes the notification; only zero consumption under regulation 33A deems the assessment done.

Software compresses the assessor’s job, because clean data shortens the review, but it cannot replace it.