2 For pedagogical simplicity, we only consider the operational energy consumption. Energy use in capital, infrastructure and other embodied energy, will be dealt with later. First, let us consider the gasoline used in automobile travel and electricity used by a household. In order to build intuition, we use energy per gallon (EPG) measured in kWh/EP drawing the analogy to the familiar energy efficiency function for automobiles—miles per gallon (MPG). EPG will be determined by the local and temporal3 electricity mix. The energy

used for driving and electricity use can be stated in terms of the common unit, EP, as4: $$ E_\textCar (\textEP) + E_\textElec (\textEP) = \frac\textmiles\textMPG + \frac\textkWh\textEPG $$ (1) Let us assume a local power generation https://www.selleckchem.com/products/netarsudil-ar-13324.html efficiency of 50 % (meaning that 50 % of the primary energy is converted

to electricity). In other words, the EPG for electricity in this region is 21.1 kWh/EP. A family that drives 1,000 miles a month in a 20 MPG car, and consumes 1,000 kWh of electricity, is expending 50 EP each for driving and electricity use. Since most people do not know their consumption in kWh but know only the dollar value of the electricity bill, we can state the energy use in terms of the expenditure reported in the monthly bill: this website $$ E_\textElec \left( \textEP \right) = \fracB_\textElec \left( \$ \right)\textEPG \cdot C_\textElec , $$where B Elec is the monthly dollar electricity bill, and C Elec is the unit cost of electricity in US $/kWh. We now extend and generalize

to include all energy services, using typical consumption (or bill) information, and making the necessary adjustments through the price to derive the total energy consumed5: $$ E(\textEP) = \sum\limits_s \left[ \fracB_s (r)\textEPG_s (r/\textEP) \right] $$ (2)where B s is the monthly consumption of resource s (electricity, water, gas etc) measured in the resource unit r (e.g., kWh, kgal, mBTU etc.). The EPG depends on the efficiency of the conversion technology. The beauty of this equation stems from several features. Adenylyl cyclase First, is its simplicity. Second, the fact that the independent variables are directly captured in see more existing measurement systems (bills), and finally EPG is typically a local (possibly personal) number. As with the MPG of a car, it is easy to build quantitative intuition around the EPG of any energy-using asset. Let us now turn to the computation of EPG for electricity generated from different primary energy sources. As a first approximation, assume all primary energy derived from fossil sources (coal, oil, natural gas) to be equivalent with respect to the losses associated with mining and extracting. The next question is how to weigh electricity according to the amount of primary energy required to generate it, taking into account the local electricity mix. Each generation type will have an associated EPG.