Posted by: nialljmcshane | May 30, 2010

Electric Vehicles: Challenges and Opportunities for the Grid.

May 30, 2010

Electric Vehicles (EVs) were another of the key themes of the Networked Grid conference that was held in Palm Springs CA on May 18-19.  In this column I will discuss the emergence of a credible electric vehicle market and some of the opportunities and challenges that this presents for the industry.

Electric vehicles are not a new idea.  The earliest electric cars emerged in the mid 19th century and, in the early years of the 20th century they competed effectively with gasoline powered cars.  Over time however, advances in internal combustion technology, reduction in noise and vibration, and other improvements led to the pre-eminence of gasoline powered cars which offered greater range and reduced fueling time compared to their electric counterparts.  EV’s continued in the form of electric powered trains and trams and in niche markets such as fork lift trucks.  There have been many attempts over the years to re-introduce the concept of electric cars but in each case, issues with charge times, battery technology and “range anxiety” – the fear of running out of power with no available charging stations nearby, have contributed to the failure to significantly penetrate the mass market.

Now, due to increased oil costs, concerns about the link between carbon based fuels and climate change, the environmental impact of oil and gas exploration as evidenced by the current oil spill in the Gulf of Mexico, and improvements in battery technology, charging infrastructure and new business models, we appear to be on the brink of a breakthrough in mass market adoption of EV’s.

The Nissan Leaf which will launch later this year is expected to retail for around $25,000 after tax incentives.  It claims a range of 100 miles although heater or AC use will reduce this.  However, Nissan suggests that the range reduction can be minimized by pre-heating/cooling the vehicle while it is still charging.  Charging options include a 110/120V 20A trickle charge cable that plugs into a regular US household electrical outlet.  For faster charging, Nissan recommends a custom installed 220/240V 40A charging dock that reduces the charge time to 8 hours.  This model works well for single family homes in the affluent suburbs.  It is less clear how this will work in apartment buildings and condominiums or in inner-city areas where few people have home garages in which to install the charging stations.  This may be another factor that leads to uneven uptake on EV’s across the territory of a utility.  A 480V quick charging capability will eventually be available but the cost of this type of charging station means that it will likely be confined to commercial charging stations and will not be suitable for home use.  Autoblog has more info on the Nissan Leaf.

Chevrolet’s research indicates that 75% of people in the US commute 40 miles or less each day and their 2010 entry into the EV market, the Chevy Volt, has a range of 40 miles but also has an onboard gas generator that can extend the range to hundreds of miles on a full tank of gas.  Charging time is quoted as 10 hours or, with a 240V charging station, as little as four hours.  Autoblog has also reviewed the Chevy Volt.

In addition to these all-electric cars, there is also a range of Plug-in Hybrid Electric Vehicles (PHEVs) including converted versions of standard hybrids such as the Toyota Prius, Honda Civic etc.  The Leaf, Volt and the PHEV’s are basic family cars.  At the upper end of the spectrum, for those EV enthusiasts with over $100,000 to spare, there is the Tesla Roadster which claims a range of 245 miles and a motor providing 288 HP, 0-60 mph in 3.9 seconds and a top speed of 125 mph (electronically limited).  Those are Tesla’s parentheses, not mine!

So with all these exciting developments, it looks like EV’s may be here to stay.  They offer lower cost to operate, reduced dependence on foreign oil, environmental benefits and a certain caché that comes with being an early adopter of the next big thing.  But, what does this mean for the electric industry?

One major concern for the utilities is the impact of the additional current drain that will be required to charge these vehicles.  It is assumed that most EV owners will opt for the 240V chargers to provide a guaranteed overnight charge.  These chargers represent a draw on the grid that is equal to or greater than an average home: the Nissan Leaf, drawing 40A at 240V represents 9.6KW demand.  The grid is architected with local transformers for every 6-10 homes on average.  One EV on a transformer probably won’t create any problems but the fear is that these vehicles will be adopted in clusters.  If we start to see 3 or 4 EV’s on a single transformer, there is a very real concern that the additional load will cause those transformers to fail, especially if the vehicles are allowed to charge during peak hours.  Demand response is a key Smart Grid solution that needs to be in place to enable the expected growth in EVs, but there are unique aspects of demand response that come into play here.

During a panel discussion on Smart Grid and Electric Vehicles at the Networked Grid event, Matthew Crosby, Regulatory Analyst at the California Public Utilities Commission noted that CPUC is working on ways to link charging of EV’s to available wind capacity.  As wind capacity ramps up, EV’s would be allowed to charge faster but when the renewable power on the grid drops, the EV charging would slow down.  This concept can be extended to integrate charging stations with residential or commercial generation capacity from wind, solar or other sources.  Community microgrids with their localized ability to control supply and demand and to shape power supply based on priority may offer a more comprehensive solution to this issue, especially if adoption of EV’s is unevenly distributed throughout the macrogrid.

New companies are emerging who are building out an infrastructure of charging stations to address the issue of range anxiety.  Some of the leaders in this field who were part of the Networked Grid panel on EV’s include; Better Place, AeroVironment and Coulomb Technologies.  More than just charging stations however, these companies are offering vehicle charging services to their customers using advanced networking technologies.

  • Coulomb believes that the value of their company is in networking and software, not hardware.  They monitor their charging stations every 14 minutes and provide an iPhone app that will guide drivers to the nearest unused, in-service, charging station.
  • Better Place offer a battery swap service in addition to charging stations.  They believe that by owning and maintaining the batteries themselves, they can extend the life of the battery by ensuring that it is charged under ideal conditions and they can eliminate the charge time concern for their customers.

The custom charging stations offered by all of these companies include sophisticated technology to implement demand response based on signals from the utility.  They also contain technology to allow the EV’s to act as distributed storage for the grid.  This technology, known as Vehicle to Grid (V2G), could in theory be used to regulate voltage on the grid or to meet peak demand without the need for peaking generators.  However, Richard Lowenthal, CEO of Coulomb Technologies stated categorically that he does not believe V2G is going to happen.  There are a number of concerns with this technology including the fact that the customer does not want to return to their vehicle to find the battery depleted as a result of V2G activity.  Other issues include the potential impact on battery life of additional charge-discharge cycles and the consequent effect on manufacturers’ warranty obligations and the fact that technically, in the current EV’s that are coming to market, the charging stations do not have a direct connection to the battery to implement V2G but are constrained to work through an on-board charger within the vehicle.  Rob Bearman of Better Place believes that they will be able to lower the cost of charging if they can generate revenue via V2G and, because of Better Place’s battery swap model, they would be in a position to provide battery storage for the grid using offline battery banks.

Matthew Crosby discussed a debate about whether CPUC and other public utility commissions who currently regulate electricity utilities have the jurisdiction to regulate the pricing structures for public, residential and commercial charging services.  Companies like Better Place and Coulomb don’t actually sell electricity by the KWh as utilities do.  Coulomb charges by time and Better Place by mile.  They argue that they are no different from other businesses that sell a product that uses electricity as an input to deliver a service (e.g. Laundromats).  The input (electricity) is regulated.  The outputs (clean, dry clothes) are not.  CPUC actually ruled on this question on May 21 and sided with the charging infrastructure providers in agreeing that the sale of electricity as a motor vehicle fuel did not make the operator of that facility a utility.  They will now move on to look at distribution grid readiness, and associated costs and benefits of various options to enable a viable market for EVs in California.

Clearly there is a lot of work ahead for regulators, utilities, charging infrastructure providers and EV manufacturers but it does appear that a new era of affordable, economical, clean energy transportation is at hand and the industry is ready to embrace the technical and business challenges and ensure mass market success for this new generation of EV’s.



  1. Nial, first of all you write so well, I wish I were 1/2 as good as you are.
    I went to local IEEE meeting and there was presentation on EV and it was very interesting. The major issues are:
    If the EV is going to take more than 10 mins to charge who is going to buy it? The only market I see is Utility Trucks they go short distances and come back and wait. School Buses do the same.
    You also did not discuss Harmonics generated due to charging and discharging. Most batteries have limited life cycles how many charges and discharges it can handle.
    Maybe I am completely off and don’t have the latest update on these issues but these are some of the major hurdles for EV’s in my opinion.

    • Matt – thank you for your kind words of encouragement.

      The two issues that you cite are indeed major concerns. I’m not sure that 10 minutes is the threshold for charge time since most charging will be done overnight or while the vehicle is parked at work. Nonetheless, gasoline powered cars maintain a clear advantage in terms of refueling time. The level 3 (480V) charging technology will significantly cut charging time by using a three phase power supply but I believe the charge time will still be on the order of 15-30 minutes. Better Place’s battery swap program is an obvious attempt to address this charging time issue. The specs for these chargers are not yet finalized.

      With regard to battery life, I am not an expert on this – it sounds like you know a bit about the factors that affect this. Some of the experts on the panel at the networked grid indicated that the main factor affecting battery life is when the battery gets hot and the charger is still trying to force charge into it. They argue that their intelligent charging stations can mitigate this problem. They claimed that intermittent charging (for example due to interruptions resulting from demand response signals from the utilities) are not a problem.

      Other problems cited included cold weather. The charging stations are designed to work down to -40 F but leaving the charging cable buried under snow is a problem.

  2. Real nice post Niall, very informative. In BYD’s literature, they boast their all electric e6 due in the US this year will have range of 239 miles and can be 50% charged in 10 minutes. Is there a Level 3 plug U.L. approved? What would be the amp draw at 480 volts to store 24 kWh (50%)battery energy in 10 minutes?

    • Thanks Keith. As far as I know the level 3 charging spec has not been approved yet. As to what the amps would be, I’m not sure on that. I believe the level 3 charger will use a three phase supply. I don’t know if that affects the calculation or if it is still just the straight P=VI calculation in which case, to push 24KWh in 10 minutes you would have to be drawing power at a rate of 144 KW which would require 300 A. Hopefully somebody else reading this can clarify if that calculation is correct or not.

  3. “Range Anxiety” is a good term. While I can provide someone a can of gas (or diesel in my case) I cannot provide someone a can of electricity for their stuck vehicle.

    Realistically, until there’s a way to drive 1,000 miles a day even with refills, I don’t see electric vehicles making serious headway in the USA. I don’t see a lot of people wanting to buy a local suburban commuter car in addition to their Dodge Caravan.

    • Thanks Jon. I cannot claim credit for coining the term Range Anxiety. It is a very real concern but, as the charging infrastructure gets built out it will become less of a concern, particularly with new business models like Better Place’s battery swap model that eliminates the charging time issue. Note also that some vehicles like the Chevy Volt have an onboard gas powered generator: even though the motor is fully electric, it can use the generator to produce electricity to extend the range.

  4. Nigel Warren in the University College London Alumni group on LinkedIn pointed to another high end electric vehicle, the Lightening:

    Unfortunately it is even more expensive than the Tesla and has a smaller projected range but…….if I had the money it would be a high class problem trying to decide which to buy 🙂

  5. […] Utility Daily article recently.  Citing some of the same concerns that I highlighted in a column on Electric Vehicles in May, Southern California Edison has developed a range of charging rate options which include a standard […]

  6. Your blogs are a newly found gem on the road to better energy sense along that information highway.
    A follow up:
    Two way plug in or V2G EVs is a problematic (as you point out) and less likely vehicle solution to an overwhelmed grid. Its cousin the HEV with 2 way plug in is the more viable and likely solution. A grid in need may be saved, for better or worse, by gasoline. at least in the interim. Down the road as V2G hybrids become cleaner and operate off bio fuels this traveling micro-ist of the micro grids could be a very big player in balancing the grid and directly meeting local needs. Indeed any hybrid some day along the road and away from the grid could have the potential to save a stranded EV.
    When the time comes your personal vehicle will have a double purpose for the same price tag. At the very least it will save your internet connection and your dinner during a brown out. When that day comes the smart grid and transportation will truly be intertwined.
    Our company is working on micro gas turbines for these very purposes.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s


%d bloggers like this: