Energy statement outline following the four step hierarchy

An energy statement outline that works follows the four step hierarchy in order and reports a carbon figure at each step. Be lean, be clean, be green, be seen. Baseline emissions, then emissions after demand reduction, then after efficient supply, then after renewables, each in tonnes of regulated carbon dioxide per year, each with a percentage saving.

That sounds mechanical because it is. The statement is checked by someone comparing your numbers against a policy threshold, and a document that gives a single headline saving cannot be checked at all. Write it so the arithmetic is visible line by line.

Baseline and the compliance target

Open with the target, not with the design. State the policy requirement that applies, the calculation methodology and version, and the emission factor set. Then give the notional baseline emissions for the development as modelled.

In London the relevant policy is Policy SI 2 of the London Plan, which requires major development to be net zero-carbon, with a minimum on-site reduction of at least 35 per cent beyond the Building Regulations baseline, and expects residential development to achieve 10 per cent and non-residential development 15 per cent through energy efficiency measures alone. Outside London, authorities set their own requirements, and plenty of adopted plans borrow the hierarchy without borrowing the percentages.

Put the baseline in a table with one row per building or block and a total. Include unregulated emissions as a separate column if the policy asks for them, and label them clearly, because mixing regulated and unregulated figures is the fastest way to produce a number nobody can reconcile.

Say which version of Part L the baseline uses. The 2021 edition tightened targets and changed the emission factors, and a scheme designed against an earlier version will produce a percentage saving that looks better than it is.

Demand reduction measures and their effect

This is the be lean section and the one that carries the most policy weight, because efficiency savings are usually the subject of a separate minimum.

Describe the fabric and passive measures with numbers. U-values for walls, roofs, floors, windows and doors. Thermal bridging approach, whether accredited details or calculated psi values. Air permeability target. Glazing ratio by orientation. Ventilation strategy and its specific fan power or heat recovery efficiency. Then the modelled emissions after these measures, and the saving against baseline.

Two habits separate a credible be lean section from a padded one. Give the measures as a specification schedule rather than as prose, so a reviewer can check the model inputs. And say what you tested and rejected, including the fabric specification that was considered and dropped on cost or buildability grounds.

Passive design belongs here too: orientation, form factor, shading, and the trade-off with summer comfort. Where the design pushes glazing towards the south, that trade-off has to be resolved in the Overheating Risk Assessment, and the two documents must use the same fabric and ventilation assumptions.

Efficient supply options considered

Be clean asks whether heat can be supplied more efficiently than by individual boilers or direct electric heating. Answer it in three parts.

First, heat networks. Say whether an existing or planned network is within a reasonable distance, name the source you checked, and give the outcome. Where a connection is not available now but is planned, describe the connection-ready provision: plant space, pipe routes and a hydraulic interface.

Second, communal or site-wide systems. A communal heat pump arrangement with thermal storage is now the common answer, and the statement should give the system efficiency assumed and the distribution losses allowed for.

Third, combined heat and power. Test it and report the result honestly. As grid electricity has decarbonised, gas fired generation has stopped delivering carbon savings in most residential applications, and air quality policy makes it harder still in urban areas. A statement that proposes it without addressing either point invites a consultee objection.

Report emissions after be clean, with the saving expressed both as a step and cumulatively.

Renewable technologies and their output

Be green is where most statements start and where they should not. By this point the demand is fixed and the supply system is chosen, so the renewable contribution is a sizing exercise.

For photovoltaics, give the array area in square metres, the installed capacity in kilowatts peak, the orientation and pitch, the assumed annual yield in kilowatt hours, and the roof plan reference showing the layout. An array shown as a percentage with no drawing behind it is the single most common weakness in a planning energy statement.

For heat pumps, state the technology, the seasonal coefficient of performance assumed, the source, and where the plant sits. Noise from external units is a planning issue in its own right and the statement should cross-refer to any acoustic assessment rather than asserting that it will be fine.

Then the emissions after be green, and the cumulative saving against baseline. This is the figure the policy threshold is tested against.

Fill every cell. An empty cell reads as a step that was skipped.

Residual emissions and any offset

State the residual regulated emissions in tonnes per year, and then the offset calculation if the policy provides for one: residual tonnes, multiplied by the period in years, multiplied by the authority's published price per tonne.

Check the price and the period against the authority's current published approach on the day you write. Both are reviewed, and carrying a figure over from last year's scheme produces an obligation that has to be renegotiated.

Where the policy does not provide for offsetting, the residual is simply the residual, and the statement should say what further measures were considered to close the gap and why they were not viable. As an illustrative example, a scheme reaching a 41 per cent on-site reduction with a residual of 18 tonnes a year, offset over 30 years, gives a straightforward obligation to draft. A scheme reaching 31 per cent with no explanation of what was tested does not.

Monitoring and reporting commitments

Be seen is a commitment rather than a calculation. Say what will be metered, at what granularity, who will hold the data, and where it will be reported.

For a referable London scheme that means the estimated figures at planning stage, the as-built figures, and in-use performance data reported through the Greater London Authority's reporting platform for defined periods after completion. Elsewhere, authorities increasingly condition post-occupancy reporting without a platform, and the statement should propose the mechanism rather than leaving the condition to be drafted around silence.

Be specific about metering. Heat meters per dwelling on a communal system, separate metering of landlord supplies, and generation metering on the photovoltaic array. Those three lines make the commitment enforceable.

Drawings and schedules to append

Appendices carry more weight here than in most reports, because the calculations are only checkable with them.

• The calculation outputs for baseline and proposed, in full, not as a summary page.
• A specification schedule of fabric and services inputs matching the model.
• A roof plan showing the photovoltaic array with dimensions.
• A plant room and riser layout showing the heat solution and space for future connection.
• A schedule of assumptions, including occupancy, hours of use and any deviation from default profiles.

Where the application also needs a Whole Life Carbon Assessment, keep the operational figures consistent between the two documents, and where a broader Sustainability Statement covers water, materials and biodiversity, let it cross-refer to the energy statement rather than restating its numbers.

And keep the Energy Statement to the structure above. Reviewers read these documents looking for four numbers. Make them easy to find.

Enter your postcode on PlanScope to see which reports your scheme is likely to need alongside the energy work.

This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. Councils usually expect an energy statement to be prepared by a suitably qualified author, and professional review is strongly advised. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.