average energyintensity improvements of around a year to are required as part of a portfolio of measures to green the energy sector consistent with a c target such improvements would result in a reduction in global energy demand by iea a halving global primary energy demand over would boost global gdp by an estimated in this effort would require an additional usd trillion investment in more efficient enduse technology but would save more than usd trillion in fuel expenditure and usd trillion in supplyside investment chateau magne and cozzi