A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described, which can supply hot water for domestic use during the whole year. The system mainly employs a bare flat-plate collector/evaporator with a surface area of 4.2 m2, an electrical rotary-type hermetic compressor, a...

This paper applies the infra-marginal analysis, which is a combination of marginal and total cost-benefit analysis, to a model with both constant returns and increasing returns in production and with exogenous and endogenous comparative advantages. It demonstrates that as transaction conditions...