Jump to content
Sign in to follow this  

Greystone EMC's announces product that could double the MPG$ of EVs

Recommended Posts

Recently Greystone EMC started offering its customer's special EV rates that will drop the cost of a kilowatt hour to about 4 cents for overnight charging.  This represents not just a 60 percent drop in cost from about 10 cents a kwh, but in the only cost comparison that changes the MPG understanding from how far you can go on a gallon of gasoline to how far you can go for the cost of a gallon of gasoline (MPG$). 

I think most people really still haven't thought much about MPG calculations since gasoline remains usually below $3.00/gallon. The current market price for regular gasoline is about $2.40.

Now EVs because they use electricity for propulsion are by design more efficient than any internal combustion engine (ICE) because the engine only captures about 25 percent of the energy contained in the gasoline to the rear wheels (if that).  With EV's more like 80+% of the energy makes it to the rear wheels.

There are a bunch of other efficiencies like regeneration instead of braking, much less mechanical loss because it has no transmission, etc.

These factors are all more or less baked into the cake in the federal figures that say this car gets 35 mpg and that one 15 mpg and this electric one doesn't use gasoline so was not comparable. The government set the standard reporting the comparable as energy, i.e. 1 gallon = 33.4 kwh.  It is that simple.  Finally, the car its self calculates a figure called miles per kwh.  If I'm out working driving to maximize my distance, I usually get about 5.8 miles per kwh.  The baseline for the car, is 4.4 mi/kwh.  If I'm pedal to the metal in a hurry and it is cold and raining, figure 2.7 mi/kwh.  Kind of like ICE cars.

The only thing missing is the cost of that energy.

That factor had a big change when the local co-op opened the gate to allow off-peak charging at a wholesale rate for EV owners.

The way to understand the impact of these rates is to think of them almost like a set of tires or some gizmo  you add to the engine that doubles the distance you can drive for the COST of a GALLON OF GAS.

So how far could my little Chevy Spark EV go on $2.40 - the cost of a gallon of gas?

Here is the formula:  Miles per kwh X cost of gallon of gas / cost of a kwh = mpg$

The story is that before Greystone made their move to make wholesale rates available, my travels were being made in an EV that was getting about 130 mpg$ ... which is pretty doggone efficient.  But use four cent a kilowatt juice instead of the almost ten-cent a kilowatt of the standard rate and quite magically the mpg$ zooms to over 300.   A rise in the cost of gasoline, like the change in kwh price under the new program, also impacts the MPG$.  If gasoline went to $3.79/gallon, my mpg$ would be over 500 electric miles I could go for the cost of one gallon of gasoline.

As the price for gasoline goes up and down the reality is that whatever car or truck you got will get so many miles per gallon.



Share this post

Link to post
Share on other sites

My dad actually has a deal with Cobb mec that nighttime charging is free (midnight to 6:00 am as I recall). It makes a lot of sense from the power company perspective as it allows the power plants to stay running around the clock which is more efficient Than starting and stopping those huge plants. 

since his solar units are running during the day, his bills are incredibly small.  

of course, you have to be able to everything you need to with just one charge or it all falls apart. 

Share this post

Link to post
Share on other sites

I'm happy to hear that Greystone Power is offering this option to allow electric vehicle drivers to further lower the cost of fuel. The down side is a much-higher rate during peak times on Summer afternoons, when your air conditioner is using a lot of electricity to cool your home. Another important equation is calculating how much electricity you expect to use to charge your car at a slightly reduced rate versus how much electricity will be used inside your home during peak summer times at twice the regular rate.

For over 5.5 years, my daily driver has been a Chevy Volt. The car is intended for short commutes with an electric range of about 40 miles before using the gasoline-powered range extender (i.e., generator). It has worked out great for me as I rarely use any gasoline. I have looked at the EV rate from the power companies over the years. However, since the battery capacity in the Volt is equivalent to one gallon of gas, I don't believe the savings from charging only at night would offset the higher rate during summer afternoons. If I had a fully-electric vehicle that would need much more electricity to charge and if I needed to charge every day, I probably would have signed up for a EV rate plan. For now, I'm still enjoying the freedom to charge at any time of day.

BTW, one perk of driving an EV in Las Vegas: Several casinos have free EV charging stations in their parking garages, usually right next to the casino entrance. Free fuel and VIP parking!





Edited by November Rain
add rate schedule
  • Like 1

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Create New...