# Economics of lighting control

Public teaching edition · 15 September 2026

Six teaching editions based on the supplied author materials. They retain the reasoning and methodology, with anonymised participant examples.

## Physical baseline

Energy in kWh = area in m² × power density in W/m² × equivalent operating hours / 1,000. Define boundaries for the sales floor, service rooms, external areas and built-in lights.

## One sales-floor example

Assumptions: 400 m², 12 W/m² and 6,000 hours a year. This gives 4.8 kW and 28,800 kWh. An additional 15% reduction saves 4,320 kWh, or RUB 43,200 at RUB 10/kWh. This is gross savings before implementation and maintenance.

## Additionality

The baseline already includes existing LEDs, sensors and automation. Prior savings cannot be counted again. Normalise changes in opening hours, area and tariff.

## Money and quality

Capital expenditure, ongoing service and accumulated savings relate to different periods. Put them into one cash-flow model. Lighting quality, technical limits and safety conditions form part of acceptance.