Mitigating Emerging EV Battery Risks
UL is innovating fast-tracked safety requirements for electric vehicle (EV) batteries that will be the basis for a new set of standards. The requirements provide safeguards today and help facilitate new applications of EV batteries.
WHY MITIGATING EMERGING EV BATTERY RISKS MATTERS
Electric vehicle (EV) sales have grown dramatically over the past few years and are projected to grow more rapidly in the future. The growth is largely a function of the environmental benefits of EVs, which are substantial. However, one of the biggest barriers to the purchase of EVs is the up-front cost, largely due to the high cost of the batteries, which make EVs more expensive than conventional (nonelectric) automobiles.1 Innovative uses of EV batteries have the potential to reduce the cost of ownership and provide additional benefits that could further advance market penetration. However, these new uses also create safety risks and underscore a critical need for new safeguards.
In the U.S. alone, more than 250 million vehicles travel nearly four trillion passenger miles each year.2 It is, therefore, not surprising that transportation accounts for one-third of U.S. carbon dioxide emissions.3 Worldwide, 13 billion tons of carbon dioxide are released annually from electricity generation, and an additional seven billion tons are released through transportation.4
The greenhouse gas emissions and carbon footprint of EVs vary, based on where they are charged.5 Charging an EV in an area with a coal-burning power plant, for example, would yield an overall carbon footprint on par with that of a high-efficiency gas-burning car.6 However, a range of studies that do “well to wheels analysis” show that EVs lead to significantly less carbon dioxide emissions overall.7
With lithium-ion battery capacity expected to double by 2025, the total cost of ownership of an EV will be competitive with that of internal combustion engine automobiles.8 However, a 2012 study shows that the impact of such a development is likely to be diminished because consumers generally do not value future savings over the higher initial cost of an EV.9
Longer term, EV battery cost may not be the issue it is today. In 2012, the U.S. government funded a five-year project at Argonne National Laboratory to develop a battery that holds five times as much energy as a standard lithium-ion battery at one-fifth the cost.10 At the present time and into the immediate future, however, the development of new applications for EV batteries can provide important ways to add immediate value to an EV and help overcome the initial cost barrier to purchase.11 These new Vehicle to Grid (V2G), Vehicle to Home (V2H) and Vehicle to Load (V2L) — collectively referred to as V2X — applications use the EV battery as a distributed generation power source to export electric power to an external load, premise wiring system, electric grid or external application.12 V2X will enable EV owners, and particularly fleet owners, to earn credits from the electric utility by feeding excess load back into the grid during peak demand periods. Other applications include using the EV battery to feed electricity to the home to reduce its utility-generated energy use or to use the EV battery as a portable generator to provide electricity for appliances such as power tools for convenience or home use during an emergency.13
With over 3,000 electric utilities in the U.S. (investor-owned, rural electric cooperatives and publicly owned), the U.S. electric power landscape and regulatory environment are complex and nonuniform — as are the technical requirements of V2X systems.14 Given the considerable interest in establishing the deployment of V2X technologies, there is a critical need for new safeguards that meet the needs of multiple stakeholders.15
WHAT DID UL DO?
As a leader in the electrical safety community, UL is at the forefront, deeply involved with the development of safety requirements for new technologies. UL has experts on each Code Making Panel of the National Electric Code (NEC) and, with the UL Electrical Council, we have a long-standing source of practical advisors on code requirements. We also have relationships with many U.S. electric utilities and a deep understanding of the infrastructure safety and interoperability issues that V2X technologies face.16
Our experience with and understanding of electric utility codes as well as product/electrical safety issues put us in an ideal position to create an Outline of Investigation — a collection of safety requirements based on our investigations of relevant products — which is the first step toward development of a Proposed Standard.17 As part of the Outline, we developed fast-tracked safety requirements to support the rapid market introduction of V2X technologies. V2X products typically involve charger, inverter and personnel protection equipment, all of which are existing technologies for which we have developed safety Standards. We had to examine how to apply what we know about the technologies to help ensure that the new uses would be safe. We worked with utilities and equipment manufacturers to identify gaps in the existing Standards created by the new uses. We then developed requirements to provide safeguards for these gaps. The requirements specifically identify the criteria necessary to certify V2X products.18
With the Outline of Investigation, UL is providing safeguards today for V2X applications. The Outline has also allowed us to begin the consensus process to formalize a new robust safety Standard that bridges the desire of automobile and inverter manufacturers to deploy new V2X technologies with the needs of the electric utility industry to protect the integrity of the grid and to ensure the safety of those who connect to it. In so doing, we are helping to facilitate new applications of EV batteries and, ultimately, helping to accelerate the adoption of EVs.19