In demand module, electric industry is usually added. But electricity generation also exists in transformation module. So does it mean emissions in demand module and transformation module woud be duplicate calculated, since energy consumptions in electric industry of demand module and in electricity generaion of transformation module are actually the same process.
To ensure you don't have double counting of emissions its best to NOT specify emission factors for demand branches that use electricity (or heat). Typically you can account for the emissions when these carriers are created in various Transformation modules. However, the emissions from direct use of fuels on the demand-side (e.g. gasoline in cars, or coal in industrial boilers) SHOULD be accounted for on the demand-side. The approach in LEAP mirrors the accounting approaches used by the IPCC in its GHG inventories guidelines.