SDG&E Charges 1,000 Electric Cars with Smart Grid

Solar EV ChargingBy John Addison (updated 9/2/11; original 5/9/11)

One Hundred Nissan LEAFs and Chevrolet Volts Added Monthly

San Diego Gas and Electric (SDG&E) may be the world’s first utility to smart charge 1,000 electric cars through a smart grid. This electric and natural gas utility, a Sempra Energy company, which services 3.4 million people, supports a growing electric vehicle charging infrastructure, expanding its electricity generation to be 20 percent renewable, and implementing a smart grid. In many ways, the three initiatives support each other.

Over 200 Nissan LEAFs and Chevrolet Volts are charging by using the utility’s smart grid. There also are a growing number of Tesla Roadsters, Prius Plugin Hybrids in test, converted vehicles and a variety of electric trucks. In addition, at the University of California San Diego over 300 light electric vehicles (LEV) charge daily to keep the campus running. At the U.S. Marine Corps in Oceanside, 291 electric vehicles are used daily, ranging from 3-ton Smith electric trucks to LEVs and e-scooters. Totaled, over 1,000 electric vehicles charge through San Diego’s smart grid using electricity generated with wind, sun, natural gas, and nuclear, not with coal power and not with petroleum.

Joel Pointon, Electric Transportation Manager gave me an update about SDG&E’s rapid progress in supporting an electric vehicle population that is now growing monthly by over 100 LEAFs, Volts, and other electric cars. SDG&E delivers electricity to homes and buildings. On the other side of the meter, companies like ECOtality, SPX, and Coulomb Technologies are installing charging units. SDG&E does not install electric vehicle supply equipment (EVSE). All investor owned utilities in California are prohibited by the CPUC from installing or owning infrastructure at this time.

EV Project to Include 1,510 Public Charging Units

The growth of electric cars is accelerated by San Diego’s participation in the DOE’s EV Project for which ECOtality is the program manager. By the end of this year, the EV Project calls for San Diego installation of 1,510 public-accessible vehicle-charging units on commercial and industrial properties throughout the San Diego region. Sixty of the units will be DC Fast Chargers capable of 60 kW charge rates. The remaining 1,450 units will be capable of 6.6 kW charging. The EV Project supports California’s clean air and carbon reduction initiatives.

The electric grid has easily supported the first 1,000 electric cars. Challenges have occurred in a number of areas. GM is expanding Volt production from 10,000 to 16,000 in 2011 and 65,000 EV in 2012 to catch-up with customer demand. Nissan had to work through software issues and then the Japan earthquake and tsunami disruption of its Oppama plant and supply chain to get on track for delivering 50,000 LEAFs in 2011.

SDG&E and ECOtality have helped train inspectors, electricians, and property managers. It has been fairly smooth to get Level 2 chargers installed in houses with garages. Joel Pointon’s team has devoted a great deal of attention to the challenge of multi-tenant dwellings where it can take 6 months to upgrade meter panels and circuit capacity in buildings where the added load of EVs was not anticipated years ago. Egos get involved in locating parking spaces when neighbors must agree to put charger parking spaces near to electric meter panel. Sometimes HOA bylaws must be legally changed.  One tenant had to give-up his treasured sauna to support the load of his new electric car.

In many cities, early adopters of electric cars give-up on getting a Level 2 charger installed and just trickle charge using a standard 110 volt outlet. For must people like me, Level 1 charging worked just fine until we finally got delivery of the Level 2 charger for our Nissan LEAF.

Smart Grid Supports Electric Cars and Renewable Energy

Lee Krevat, SDG&E’s Smart Grid Director, gave a keynote speech at Network Grid 2011 by Greentech Media. Mr. Krevat outlined the status of SDG&E’s smart grid, showed how it supports electric cars, and even shared his experience as a personal driver of a Nissan LEAF.

Electric cars have not caused problems for San Diego’s grid because the utility has already dealt with the greater challenge on integrating thousands of solar PV installations. SDG&E has made its grid smarter and more reliable to deal with the intermittency and the extreme voltage fluctuation inherent in PV. By 2010, 35 circuits had greater than 20% PV; by 2016, 155 circuits are forecast.

SDG&E has completed the first step in upgrading to a smart grid with AMI, installing over 1.4 million ITRON smart meters with Zigbee chips. Now it is detailing and implementing a smart grid plan. The plan must be complete by July 1 to comply with California law SB17. The plan includes:

  • Vision
  • Baseline
  • Strategy
  • Security
  • Roadmap
  • Cost
  • Benefits
  • Metrics

Beyond AMI, it is San Diego’s information technology initiatives that make the grid smarter. SDG&E is admired by other utilities for its geographical information system, winning the GIS Project of the Year Award by DistribuTECH for the Virtual Integrated Situational Awareness project. The GIS system shows the location of each transformer and the number of EVs supported by transformer. SDG&E uses predictive models to add transformers before they overload. LEAF and Volt buyers who opt-in with Nissan and Chevrolet, let the utility see where new electric cars will be located, so that transformers and infrastructure can be added. The utility’s proactive approach is in stark contrast to most utilities who have taken no action in preparing for EVs, or who are sounding alarm and asking for PUC approval for rate-based investment before taking any action.

So far, San Diego’s networked grid is handling the electric car charging without problems. Most transformers only support zero or one electric car. Some support two. New transformers are much smarter than old. Trucks no longer need to be rolled to get equipment specs. Transformers are becoming smart enough to better isolate faults, better balance voltage, and even model whether load is coming from an electric car or air conditioner.

San Diego’s Director of Asset Management, Smart Grid Projects, Vic Romero walked me through other smart grid enhancements. Distributed automation (DA) is being upgraded. Fault isolation, realtime response, and prediction capabilities have been upgraded. SDG&E initiated a project that combined data from wildfires, lightning strikes, earthquakes, wind forecasts and SCADA data to provide a real-time situational awareness dashboard for visualization in the control room and boardroom alike.

The idea came after SDG&E experienced the San Diego wildfires in October 2007. During those devastating wildfires, SDG&E activated the Emergency Operations Center (EOC) in which all key representatives from the company come together to monitor events, communicate and make decisions. Old approaches of rolling trucks, emailing messages and faxes are giving way to thousands of networked sensors and smarter distributed assets communicating over a smart grid to the new GIS system. SDG& not only uses the data to make predictions, it even has its own weatherman.

Electric Car Charging Gets Faster in 2012

So far, Volts and LEAFs are only charging at 3.3 kW/h. Next year, 2012 LEAFs, and new battery electric cars from Ford, Honda, Mitsubishi and others will double that to 6.6. SDG&E feels confident their smart grid will handle the load and that predictive approaches will keep them ahead of EV charging. SDG&E Electric Vehicle Site

Faster charging, however, takes serious investment. New infrastructure is needed for the 440 volt DC fast charging. Some automakers fear that millions of electric cars will not be charged unless Level 2 charging gets upgraded to 19.2 kW, which put load demands beyond the solution of adding a new transformer here and there.

By 2020, San Diego plans to be distributing 22 TWh of electricity in contrast with 16 TWh in 2010. 33 percent of that 22 TWh will be renewable energy, including over 2 TWh of wind that is most available at night when several hundred thousand electric cars will be charging through one of the world’s most advanced smart grids.

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About Author: John Addison

Founder of the Clean Fleet Report, author of Save Gas, Save the Planet. John writes about electric cars, renewable energy, and sustainability.

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