# How do I turn litres of diesel into megawatt hours for the energy table in the European Union (EU) voluntary standard for small companies (VSME)?

Canonical: https://senseible.earth/answers/vsme-b3-litres-of-diesel-to-megawatt-hours

Multiply litres by the fuel's density to get kilograms, then by its net calorific value to get energy, then convert to megawatt hours (MWh). The standard's example uses 0.84 kilograms a litre and 43 terajoules per gigagram, near 0.01 MWh a litre. VSME is the European Financial Reporting Advisory Group's Voluntary standard for non-listed micro-, small- and medium-sized undertakings.

## Why a conversion is needed

Disclosure B3 asks for total energy in megawatt hours. Your invoice says litres. Your invoice counts litres and your bill counts units. They measure different things, like a count of buckets and a weight of sand. Both must become energy before they can be added.

## The three steps in the standard

1. Convert litres to mass: litres times density, in kilograms a litre.
2. Convert mass to energy: tonnes times the net calorific value. Net calorific value is how much heat a tonne of the fuel gives when burnt, with the heat locked in the water vapour not counted. The standard says it can be a typical value from a reliable source such as the Intergovernmental Panel on Climate Change (IPCC), or one given by your supplier or worked out by you.
3. Convert to MWh: 1 terajoule (TJ) = 277.78 MWh.

## The standard's own diesel example

- 4,456,000 litres x 0.84 kg a litre = 3,743,040 kg, which is 3,743 tonnes.
- 3,743 tonnes x 43 TJ per 1,000 tonnes (43 TJ per gigagram) = 160.95 TJ.
- 160.95 TJ x 277.78 = about 44,709 MWh (the standard prints 44,708).
- The text prints the middle figure as 3,43,040 kg, a typing slip. The product is 3,743,040 kg, and the standard's 3,743 tonnes matches it.

## What to watch for

- Density and net calorific value change a little by supplier and batch. The standard allows your supplier's figure. The 0.84 and 43 are the standard's example numbers, so use your own if you have them. Other diesel densities, such as 0.832, are in use; the answer moves by about 1%.
- Do this per fuel. Diesel, petrol, furnace oil and coal each have their own values.
- Add the converted fuel to the fuels row of the energy table. Electricity stays in units from the bill. If your units are in kilowatt hours, divide by 1,000 for MWh.

## Example: a smaller diesel purchase

- Bought: 10,000 litres
- Mass: 10,000 x 0.84 = 8,400 kg = 8.4 tonnes
- Energy: 8.4 x 43 / 1,000 = 0.3612 TJ
- MWh: 0.3612 x 277.78 = about 100.3 MWh (so about 0.01003 MWh a litre)

Density 0.84 and 43 TJ per gigagram are the standard's example values. Use your supplier's if you have them.

## What Senseible does here

Senseible reads fuel invoices and electricity bills into records, so the fuel and units you bought are on file for this disclosure. Tank dips, plant logs and meter readings stay with you, or can be connected as a custom meter integration on request.

- [What is the VSME standard?](https://senseible.earth/answers/vsme-standard-for-small-suppliers)
- [Which do I count, DG diesel or DG units?](https://senseible.earth/answers/dg-diesel-and-dg-units-double-counting)
- [Fuel tank dip readings for emissions](https://senseible.earth/answers/fuel-tank-dip-readings-for-emissions)
- [Free calculators](https://senseible.earth/calculators)

Sources: [European Financial Reporting Advisory Group (EFRAG), Voluntary standard for non-listed micro-, small- and medium-sized undertakings (VSME), 2024 edition, 66 pages, paragraphs 29, 86 to 89](https://www.efrag.org/sites/default/files/sites/webpublishing/SiteAssets/VSME%20Standard.pdf)

Last reviewed 2026-11-07. Facts are from the standard's own text, with the paragraph numbers named in the source line. The European Commission adopted its own standard for voluntary use in a Delegated Regulation of 3 July 2026, which is not in force until it is published in the Official Journal and may differ from this text, so ask your buyer which one it means. Our own readings are marked as such.