The en.lighten initiative has developed two separate global lighting market models – one for on-grid and another for off-grid lighting.

The on-grid lighting model estimates the installed stock by two independent methods, one based on lamp shipments and one based on electricity consumption for lighting. These two approaches are averaged together to arrive at an estimate of the installed stock in each country.  National data such as electricity prices and lamp prices are then used to estimate the payback period and national financial benefits. The power generation mix for a country is used to calculate the CO2 savings and other air quality benefits associated with the transition to energy-efficient lighting. More detailed information for the on-grid Country Lighting Assessments can be found here.

The off-grid lighting market model estimates the fuel-based off-grid lighting energy consumption and savings potential derived from replacing kerosene lanterns, candles and torches (flashlights) with solar LED lanterns, based on a one-for-one replacement. The model incorporates electrification rates, GDP, population, fuel prices and other inputs.  The model also assigns off-grid technology mixes on a per-capita basis based on a sample of country studies. The CO2 savings are calculated based on the combustion data for kerosene and candles, and a life-cycle assessment of dry-cell batteries (for torches).  More detailed information for the off-grid Country Lighting Assessments can be found here.