If you need to calculate the GHG emissions associated with employees working from home, this spreadsheet of homeworker factors gives you a homeworker emission rate per day for over 219 different countries.  The factors take into consideration the need for heating / cooling per country; the electricity factor per country and the percentage of GHG emissions which can be attributed to homeworking. Along with the comprehensive list of global factors, you will also receive a detailed white paper which explains the methodology behind the calculations.
 
You can buy and download these factors separately or as a bundle.  These factors are valid for a year and must only be used for your own business use.