EVs and the Smart Grid Go Together in Chattanooga, but Few Other Places
Whenever utilities talk about charging electric cars, they invariably invoke the smart grid as an essential ally in their case. Indeed, for a number of reasons it's hard to imagine EVs having a smooth landing on the roads of America with the clueless and dumb power grid we have today. That's why a visit to EPB, the municipal utility for Chattanooga, Tenn., -- which gets its power from the Tennessee Valley Authority -- was both disturbing and enlightening. EPB will have synergy between EVs and its smart grid, but most other places probably won't.
Plugging in an EV is like adding a new house to the grid, utilities say. And EV ownership is likely to be concentrated in certain upscale zip codes (they're expensive), which raises the possibility of overloaded transformers in some neighborhoods while others are barely touched. The problem is compounded if everyone plugs in at the same time (at say, 6 p.m. when people get home from work).
The smart grid addresses this by allowing interactivity between owners, cars, and utilities too. If a plant operator sees a brownout coming on a hot day, they can, with their owners' consent pull some charging EVs off the grid, deferring them until the evening hours. They can even use some of the energy stored in the EVs' batteries to add electricity back into the system.
Chattanooga is a host for the federally supported $230 million EV Project, which will put 300 free EV chargers on its streets. It will also be among the first U.S. communities where the Nissan Leaf (to be built in nearby Smyrna) is being sold. Luckily, EPB is also rolling out the country's most advanced fiber-optic smart grid.
According to Danna Bailey, an EPB vice president, the company began preparing its smart grid work in the 1990s and with the help of a $111 million Department of Energy matching grant from stimulus funds announced last last year is now on track to roll out a blazingly fast 150 Mpbs 100 percent fiber-optic smart grid by December. "The grant didn't change our plans, but it turned an eight to 10-year fiber-optic rollout into a three-year one," Bailey said.
Unfortunately, few other utilities around the country are as advanced. The sad truth is that most are talking, talking, talking about the smart grid (it makes great headlines), without a fast-track plan that will have one in place for the EVs rolling out late this year and early next. Chattanooga shouldn't have this problem.
Most utilities today have no idea how much electricity individual customers are using, and finding the source of blackouts involves not looking at a computer screen but sending out search parties -- what EPB calls "truck rolls." Ryan Keel, an EPB assistant vice president of electric systems with a specialty in the smart grid, said that his company is better than most utilities in actually being able to monitor the health of its 115 substations (each serving 2,000 customers). But it currently can't see beyond that and track electric load in the homes themselves. So if all 2,000 consumers plugged in electric cars simultaneously today, the system would flash red danger lights but there'd be no way of knowing what had caused the problem.
"Smart meters will allow us to collect incredible amounts of data," said Bailey. "Right now we take in two million data points per year, but by the fall of 2012 it will be six billion data points annually." There are 7,000 smart meters (which give consumers unprecedented information and allow utilities to check the current flow from HQ without meter readers) installed in Chattanooga now. But they'll soon be deployed at a rate of 1,500 per week. "People will be able to monitor the electricity use of their toasters if they want," Bailey said.
EPB's Diana Bullock said that work on where the 300 electric charging stations will go is underway and ahead of schedule. "We're gathering input from the community, working with the mayor's green team. We'll definitely have a station at our downtown building, and we want them where people work and play, and at shopping centers."
According to Keel, EPB is working with the industry-supported Electric Power Research Institute (EPRI) on a study that should give useful information about how adding EVs to the distribution network will affect the grid. Keel said, "We're asking questions like, 'How do we recover our money from people who recharge at our stations?' And, 'If we put chargers at gas stations, how do we get around the fact that the owners of those stations can't sell electric power?'"
These are indeed the kinds of questions we need to ask -- they're right up there with figuring out how to recharge cars owned by urban apartment dwellers. Chattanooga's pioneering smart grid doesn't answer all the questions or solve all the issues raised by cars with long charging times and short range, but it's a huge help.
Related:
Photos: EPB. Jim Motavalli