Every building is a complex system. Seemingly inconsequential and difficult-to-identify building attributes can have an outsized impact on energy consumption, skewing our understanding of the overall building performance. So why don’t industry-standard best practices for building energy modeling account for those kinds of nuances? After decades conducting audits, I began to ask myself this question […]
Questioning a widely accepted standard for energy engineering is not to be taken lightly. Yet in 2014 I found myself doing just that. While collaborating on the Department of Energy-sponsored Building Asset Rating (BAR) program, my faith in the gold standard of energy analysis was shattered. In the process, I came to the conclusion that […]
E10 fuel (90% gasoline/10% ethanol) has a source energy, which is reduced due to extraction, processing and transport, to become the primary energy fed to E10 vehicles. As a result, the energy fed to the tank has to be multiplied by 1.2639 to obtain source energy.
Electrical energy has a source energy, which is reduced due to extraction, processing and transport, to become the primary energy fed to power plants, which convert that energy into electricity, which after various losses, arrives at use meters. As a result, the energy fed to the meter has to be multiplied by 2.995 to obtain source energy.
The below “40 mpg, EPA combined” table shows, high-mileage E10 vehicles, including hybrids, such as the 52 mpg Toyota Prius, have greater energy efficiency than EVs, and only slightly greater CO2 emissions than EVs. It would be much less costly and quicker to significantly increase the US hybrid fleet, than to build out the EV fleet, which is still in its infancy, and would require major, expensive changes to supporting infrastructures.