This post is the first in a series explaining how fleet electric vehicle operators can save money charging their EVs. I’m breaking the concepts down into smaller pieces to introduce the concepts to both new and experienced energy managers. For some, these concepts will seem overly simplistic, but I hope to offer easy to understand pieces to help all readers.
Electric Vehicles (EVs) offer the promise of tremendous operating savings on several fronts. In most places, it’s cheaper to “fill-up” an EV than a gas or diesel. Also, the GHG emissions from an EV are lower than a gasoline or diesel vehicle. * However, the cost of charging an EV varies based on where and when you charge it. Each utility offers different electric rates that vary by location and often time of day when used and the peak amount (kW) consumed. This post will focus on one aspect of those utility tariffs – peak charges.
We’ve all experience that nauseous, lost feeling when looking at an electric bill. The only clear part is the number following the dreaded words, “Amount Due.” There’s a bunch of other numbers that magically appear and make up the base charge that’s added every month. In most rate tariffs, a part of that base charge is set annually depending on the peak amount of electricity used (peak demand).
The utility logic here goes like this, “We have to be ready to meet your needs all year long. Therefore, we have to build and operate assets to be ready for you at a moment’s notice. Since we need to be ready all year long, we’re going to charge you all year long just in case you decide to make today your peak day.” In a dream world, a facility would use a level amount of power all year long, but in a real world there’s a day where a building sets its annual peak. For most buildings those peaks are caused by summer afternoon HVAC loads. EV charging loads on top of the cooling load can push this peak higher and result in a larger base charge for the entire year.
EV Peak Load Management -PLM – is the active steps taken to reduce the peak load contribution from EV operations. It can take the form of scheduling charging for another time or charging at a slower rate. So far it sounds so easy . . . .
In upcoming posts I’ll discuss different methods of EV Peak Load Management (“PLM”), operator specific needs and wants, impact of battery chemistry, Demand Response and how Control Dynamix EvAuto and EvMetrix tool sets control the cost of EV charging.