Bi-directional charging technology is used not only for charging electric cars, but it can also send the energy stored in the car’s battery back to the building or the grid. Now Nissan Leaf owners equipped with the Fermata Energy FE-15 bi-directional charger can also take advantage of that functionality. According to Nissan, use of the approved charger will not impact the Nissan LEAF’s battery warranty.
The Fermata Energy Demand Charge Management application that works with the FE-15 charger continuously monitors a building’s electrical loads, and may draw on the Nissan LEAF’s energy to provide power to the building during high-demand periods when energy costs are high. In states with utility demand response programs, bi-directional-enabled Nissan LEAF vehicles (2013 and later) are able to safely send energy stored in the battery to the grid during peak energy demand times, such as in summer months.
“We applaud Nissan for their ongoing leadership in delivering new, meaningful technologies to EV owners. V2X bidirectional charging is an important innovation that enables Nissan LEAF owners to create additional value from the energy stored in the vehicle’s battery. That value helps reduce the total cost of ownership of their car, while supporting grid resilience,” said David Slutzky, CEO and founder of Fermata Energy. “At Fermata Energy, we were the first to receive the UL 9741 certification in the world and now the first to have Nissan’s approval on a bidirectional charger in the U.S.”
The Fermata Energy bi-directional chargers are installed at multiple sites across the United States. In Colorado as part of a vehicle-to-build (V2B) program, the Fermata Energy platform has lowered the electric bills at the Boulder North Recreation Center, saving the city on average $270 per month, the approximate cost of leasing a Nissan LEAF in some markets.
The International Energy Agency (IEA) conservatively estimates that 130 million electric vehicles (EVs) will be on the road globally by 2030. Bi-directional plug-in electric vehicles (PEVs) offer an opportunity to support the grid, enhancing security, resilience and economic vitality. A bi-directional EV fleet could serve as both a clean transportation as well as an energy storage asset that could also create new revenue opportunities for EV owners or fleets. Fermata reports that the FE-15 bidirectional charger is available for commercial and government fleet owners.
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I wonder if there is an energy loss in charging from the grid, then sending power back onto the grid, and then recharging the car battery again. I still don’t know if the losses are great using solar to charge a residential battery bank, and then using that power to charge a car battery – as opposed to directly charging the car from the solar array. And then the utility would best to use a dedicated battery bank when possible, and taking power back from vehicles only in an emergency situation.
Gordon, here is what an IEEE study found. . . “Abstract:
The business case of vehicle-to-grid (V2G) technology and its potential to provide grid services is heavily dependent on the round-trip efficiency of this technology. Surprisingly, very little empirical research is conducted to determine the V2G round-trip efficiency of electric vehicles currently available in the market, resulting in a wide range of efficiency values used in V2G modelling studies. This study aims to create more insight in the current V2G round-trip efficiency to stimulate that more uniform and realistic efficiency values are used in other studies. A field experiment is executed to measure the round-trip energy efficiency of V2G for different dates, current rates and average state of charge. It was found that the average round-trip efficiency (i.e., combined inverter and battery efficiency) when charging between a state of charge 25% and 75% with 3×16 Ampere was 87.0%(±1%). However, various external factors could influence the measured efficiencies, which had a total range from 79.1% to 87.8%. Charging at lower ambient temperatures and lower current rates had a statistically significant adverse effect on the round-trip efficiency. Efficiency at high and low state of charge was found to be marginally lower than around medium state of charges. Two different electric vehicle + charging station models were tested, one with on-board AC/DC converter, which is a novel V2G setup, and one with external AC/DC converter, rendering no statistically different efficiency values.”
Thanks Dan
Charge Controller losses, Chemistry charging losses of the different types of batteries grid tied inverter losses from battery to grid can add up to 30% in losses on lead Acid deep cycle Marine/ RV batteries like I use in my system. I am told lithium ion has less battery charge and discharge losses depending how full the batteries are at the time of charging just like lead acid batteries. However, utilities are giving deep discounts from 1:00AM to 11:00 am of about 30% on the charging electricity for EVs and some pay a bonus for electricity given to the grid from 4:00 PM to 9:00 PM that could be greater in value than the losses in the charge to discharge cycle. Keeping one’s home powered in a black out is priceless.
The biggest cost will be the power box that the auto manufactures supplies to do all this and related additional electrical wiring needed to power the home in case of a power failure with transfer switches and all. How many times a year would the feature be needed or used would be the determining factor to just not getting a few UPS units placed around the home for power backup.
Thanks for commenting. The power rarely goes out in my location – maybe 1 time in 10 years has it been out for long enough to have spoiled the food in the freezer, which is the main priority of my home system. I too am using AGM lead/acid batteries – and I really avoid cycling my battery bank deeply. I think I wish to use something like lithium batteries in the future, or sooner if I could figure out how to combine the 2 systems. If I increase the size (currently about 1/2 kw), I would like it to supply some of my transportation needs. It gets complicated, and not something my wife would like to learn and babysit.
The Leah has been used for about 10 years in Japan for V2B. It will be great to have it in the U.S., especially during a power outage at home.
However, this electricity is not free. The battery degradation caused by the cycles the battery is put through in such a configuration impacts the Leaf’s owner. As a corollary, my Nissan Leaf originally had a range of 109 miles when new. After 46,000 miles and 3 & 1/2 years of daily use/cycling, the range dropped to 77 miles. When I sold the Leaf, the replacement battery cost was $6,000 (much more than the second-hand battery market price of $800 for the Prius I also owned). The Leaf’s used car sales price was impacted heavily, primarily by the reduced range.