What If We All Drove Chevy Volts?

I wrote a previous post showing how purchasing a Chevy Volt to offset gasoline prices doesn’t make financial sense based on the current Volt purchase price and gas prices less than $7.00 per gallon.  I also stated that I am opposed to purchasing a Chevy Volt on principle because the US tax payers are on the hook to the tune of a $7,500 rebate for every purchase and I still stand by that assertion.

There is no need to rehash those arguments here but there was a recent comment by JustAddValue to my blog post that raised an interesting question that I’d like to explore in this blog post.

“One other issue I see is that America does not have the electrical capacity infrastructure to support tens of thousands (let alone millions) of EVs currently. Our Transmission and distribution systems are in deplorable shape and would need a significant upgrade to allow for future capacity. That’s a fact.”

The reader posed an interesting question.  What would be the impact to the US power generation industry if every American drove a Chevy Volt (or similar electric vehicle-EV) for their primary vehicle (commuting to work, driving to vacations, running errands, etc.)?

Before we can answer this question we first need to understand the difference between kilowatts (KW) and kilowatt-hours (KWh) and there is a great website you can use here but if you don’t have 20 minutes to read this article, let me give you the condensed version.  Power is expressed in KW and this is the capacity to produce power that can be converted into energy which is expressed in KWh.  The amount of energy used is based on the power (KW) times the time (Hour), hence KWh.  Power plants are usually rated in the amount of power they can produce but we are charged for the amount of energy we use so that is why your commercial and residential energy bills are expressed in KWh.


In the previous post I showed where the Chevy Volt requires 12.9 KWh to recharge its battery so we’ll use that figure in our calculations.  From this website, we see that in 2010 the US had a total installed electrical generation capacity of 1,120 GW (1 Giga watt is equal to 1,000 Mega Watts or 1,000,000 Kilowatts).  From this website, we see that in 2010 the US consumed 4,125,060,899 MWh (or 4,125,061 GWh).

From this website, we learn that there were over 250 million registered vehicles in the US in 2010 but just using small and large cars for our analysis (“light duty vehicle, short wheel base” and “light duty vehicle, long wheel base” as defined in the table) we see that there are 230,444,440 cars that meet that criteria.  Let’s assume that 75% of these cars are actually used as primary vehicles (the rest are either idle or rarely driven) so that gives us a total of 172,833,330 cars that will theoretically be replaced with Chevy Volts or a similar EV.


Now I can perform the calculations and they are shown below:

We see that if every American drove a Chevy Volt for their primary transportation vehicle we’d use an extra 8.3% of the total installed electrical power generation capacity and we’d increase our yearly electrical energy consumption by 19.7% (round it up to 20%).

Using these theoretical calculations, we can conclude that we probably would not have to install new electrical generating facilities because we only use 42% of our installed capacity right now (4,125,060 divided by 9,811,200) but, using my engineering background as a guide, you never operate a plant at 100% of capacity due to inefficiencies so the electrical power generation industry is probably operating much closer to full capacity than the theoretical 42%.  Power plants don’t continuously operate at peak power so taking the installed power capacity and multiplying it by the total number of hours in a year (as I did on the spreadsheet) is also not realistic.  For these reasons, I won’t use the “% of installed energy capacity” metric but instead use the “% increase in US energy usage” metric since that is the amount of extra energy that the power plants would need to produce to satisfy all the new Volt owners.

I want to restate the results of my calculations again for effect and I’m just going to just focus on the % increased US energy usage metric.

If 75% of all passenger cars were magically converted to Chevy Volts then the annual US energy usage would increase by 20%.

You don’t have to be an engineer to realize that increasing all US electrical power generation plants by 20% would not be a trivial exercise!   Attempting to raise US energy output by 20% raises many issues/questions that I’ll get to shortly but first a quick side bar for the Al Gore cult.

Here’s an interesting little wrinkle for the Green crowd – Increasing our electrical energy consumption by 20% would result in approximately 15% more Greenhouse Gas (GHG) emissions from power generation plants because around 72% of our fuels we use to produce electricity are comprised of coal, oil and natural gas as is shown on this website.

Does this increased amount of GHG from increased electrical power production offset the GHG emissions from burning gasoline in cars?  I don’t know the answer to this question but I really don’t care either because the whole Anthropogenic Global Warming argument can be thoroughly debunked here.   I only mention this because much of the demand for EV’s is generated from the environmentally conscience crowd who wishes to reduce their carbon footprint.  Have they performed this calculation which proves that driving an electric vehicle reduces their carbon footprint when considering that they are using GHG producing fuel to recharge their vehicle?

What I’m more concerned with are the consequences from having our electrical power generation grid production increased by 20%.

What impact will this have on US power generation plants?

How much more will each KWh cost as a result of this increased demand?

Will this new energy demand help increase the number of nuclear power plants in the US?

Is the Green cult comfortable using nuclear power plants to recharge their electrical vehicles?

What strain will this put on the coal mining industry?

Can our current power distribution network handle this increased load (transformers, substations, distribution lines, etc.)?

I would love it if we could kick OPEC to the curb and eliminate our dependence on foreign oil for our transportation needs but have we thought through the ramifications on the electrical power generation sector if we continue down this path of EV adoption?  I know this transition won’t happen overnight (and if the Federal Government is in the business of leading this initiative then it’ll never happen!) but a thorough analysis needs to be performed before we move further down this path.

Are we prepared to absorb an increase in electrical energy productionof 20% or more once we switch over to EV’s?


Addendum – You can double check my calculations using my spreadsheet – chevy volt energy usage

This entry was posted in Climate Change, general science, politics. Bookmark the permalink.

10 Responses to What If We All Drove Chevy Volts?

  1. Volt Driver says:

    Ugh. Once again you are tackling something that is so technical, you might as well not even try and just use the vast amounts of studies that are alreadyavailable. You are not the first person to think of this, and scientists and industry experts have already weighed in many many times. Many studies basically state: ‘Electric vehicles can be accepted into the grid in significant numbers given the nature of their slow roll-out, their use of off peak power generation, and the smart technologies that are being developed to reduce their charging capacity based on grid overload.’

    In addition, U.S. power consumption is already rapidly growing. Electric cars are going to be a drop in the bucket compared to other growth areas. Yes, the U.S. power system faces challenges, but they will have to be overcome, regardless of electric cars or not, as our excess grid capacity is nearly gone.



    • cosmoscon says:

      Wow, you link to a 100+ page report talking about how to handle this increased load to the power grid and you say that EV’s are a drop in the bucket? Even the 2nd link you provided echoes my conclusions above:

      See page 11 – “Overall, the projected electrification of light-duty vehicles in North America poses a challenge to the electricity grid while also offering unique opportunities.”

      Neither study you linked to performs the calculation that I did in this post – assume a 100% adoption of EV’s – so you obviously didn’t read my post before jumping to comment on it or you didn’t understand it.

      Other than that, your comments were right on topic!

      • patb2009 says:

        “In addition, U.S. power consumption is already rapidly growing”

        The upstream commenter reflects a common myth, actually US Electricity consumption is decling per capita and per rata.

        LED Lights, more efficient sensors, clever controllers. They are all dropping power demands. US Power demand has been stagnating for years.

  2. Theoden says:

    Cosmocon, while I can appreciate the information illustrated in your calculations, electrification of the US passenger fleet is not as one dimensional you depict. Even if EV vehicles dropped down to 25K per unit, it would take a considerable amount of time to work IEC vehicles out of existing inventories. We will not have to increase our power all of sudden just because a few million EV’s are on the road. Second, you are correct in your assumption that the Volt takes ~13KWH to charge from a state of being empty however, not every electric vehicle being charged will be in an exhausted state. I own several cars and one of them happens to be an EV. On a day to day basis, I, like many other EV users, do not use all of the charged battery power. Therefore, I usually top off my EV’s charge at around 2-6 kWh a day. Using the full ~13kWh charging requirement as a basis for your calculation depicts a worse case scenario that would probably never happen in the real world. The use of a charging kWH average would make more sense in your illustration.

    As far as increasing the US power grid by 20%, that number, too, is inflated. As I mentioned in a previous thread, your use of a kWhs is totally up to you. Just because one owns an electric car, does NOT mean that they adding an increase of reactive/resistive load on the public grid. This is where your assumptions fall flat. You have assumed that the EV’s would be an addition to daily consumption and not offset in full or in part by conservation – aka a change in a consumer’s consumption habit. I have been tracking my power consumption for 6 years and I can tell you that my EV has not increased my kWh usage. How did I achieve this miracle you ask? Easy, my average daily kWH for my home is 40-56 kWh (depending on the season) so I decided to do a little homework to see where my home energy hogs were. First culprit and no surprise, the HVACs, use more electrical power daily than one full charge on my Volt. In fact, nearly 74% of my annual kWh consumption is for heating and cooling. To offset an kWh increase from the charging my EV, I simply dropped or raised my programmable thermostat by 2-4 degrees and consolidated my laundry and dishwasher runs until I achieved a net zero state for EV charging. My local utility did not have to add another gas fired generating station, I did not have to pay for anything extra, and my bills have actually decreased.

    I do not believe that electric vehicles are for everyone and for all applications however, I do believe that they are a good fit for folks who drive less than 40 miles a day.

  3. sandeen says:

    You say: “If 75% of all passenger cars were magically converted to Chevy Volts then the annual US energy usage would increase by 20%.”

    Even if all your calculations are correct, it doesn’t support that statement. ELECTRICAL usage might increase by that much, but not ENERGY usage. It’s just using a different fuel source (modulo efficiency differences) (with all the challenges that may pose for the existing grid).

    I see from the rest of the post that you do mean electrical, but your bolded “takeaway” is inaccurate, just FWIW.

    I was actually trying to calculate how much extra electrical capacity we’d need if every passenger mile was driven in a Nissan Leaf (34kWh/100 miles according to the EPA) and my first cut came out to something that sounds pretty manageable, but I need to double check my numbers… I’ll try the same with a Volt, and see what I get.

    • cosmoscon says:

      Thanks Sandeen for stopping by and commenting. Yes, you are correct that I was only talking about Electrical energy production and you were right to point this out.

    • sandeen says:

      I think a potential flaw in your calculations might be that it assumes every one of the 75% Volts will be charged exactly once per day, without taking into account how far the passenger fleet actually drives in the US… but let’s see.

      According to http://www.eia.gov/emeu/rtecs/chapter3.html the US saw 1,793 billion passenger miles driven in 1994; let’s round it up to 2,000 billion passenger miles for 2012 (just a ballpark guess) And, according to fueleconomy.gov, the Volt uses 36 kWh/100 miles driven. Leaving aside for the moment that not all Volt miles are electric….

      So 2,000 billion miles/year / 100 miles * 36 kWh = 720,000,000,000 kWh per year, or 720,000 GWh/year, or 1,972 GWh/day. Ok, so you were in the right ballpark at least. 🙂

      Now, 2,000 billion miles per year is about 5.5 billion miles per day (holy cow!). Could the Volt fleet cover that much daily in electric mode? If your model is right and there are 172,833,330 Volts, that’s about 32 miles per Volt per day, just under its electric range. So yeah, they could do that, though it’s ignoring the longer highway trips which would run on gasoline.

      So this does indeed sound like a lot. But here’s one other possibility: if you need 13 kWh per day to charge a Volt, you could average that much output from about a 3.5kW solar PV system on your garage, even in a middle-of-the-road solar resource like we have in Minnesota. (My system averaged about 3.5kWh per kW of panels for 2011, somewhere like CA or AZ would require less.) With solar PV approaching $6/watt in 2012, $21,000 worth of solar PV could keep your Volt(s) fueled up for 20-30 years. That kind of distributed generation makes more sense to me than trying to add 1000GW of centralized capacity.

      It is a daunting problem, to be sure, but as more of the world wants personal transportation, I’m convinced that we’ll either need to find new efficiencies or new fuel sources; I don’t think oil is going to cut it indefinitely. Thanks for the thought provoking article.

      • sandeen says:

        Sorry that should have been “My system averaged about 3.5kWh PER DAY per kW of panels for 2011.”

      • sandeen says:

        And OK last post 😉 If you want to know how Volts perform in the real world, check out http://www.voltstats.net/ … love ’em or hate ’em I think it’s cool that over 2000 owners have put up real-world data (for example, about 80% of the miles recorded there were in EV mode, 20% in gas mode)

  4. cosmoscon says:

    Thanks again Sandeen for adding to the conversation and proving that this is a very complex topic. I love data and thanks for showing us a link to the Volt Stats website.

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