A Substation in Time Saves Nine

Photo credit: Dominion

The 2013 sniper attack on Pacific Gas & Electric Company’s Metcalf transmission substation was a wake-up call for the electric power industry. A team of riflemen knocked out the facility near San Jose, Calif., by firing upon and severely damaging 17 transformers. Thanks to redundancy in the grid, PG&E was able to prevent blackouts by re-routing electrical power. But the incident drove home how vulnerable the electric grid is to sabotage.

“The next day,” recalls Mike Lamb, manager of operations engineering for Dominion Energy Virginia, “we started brainstorming about what resiliency improvements we needed.”

As part of a multi-pronged strategy to bolster resiliency of its 6,500-mile electric transmission lines, 57,000 miles of distribution lines, 900 substations and 66,000 transformers, Dominion procured mobile transmission equipment designed by manufacturers in Europe, Asia and North America. The mobile equipment provides a “plug and play” design that allows it to connect with high-voltage cables in a fraction of set-up time required by conventional technology.

Most of the equipment held in resiliency reserves sits idle until needed in the aftermath of a hurricane, earthquake, or human-caused event. As it turned out, has Dominion found a use for the trailer-borne transmission outside of an emergency situation.

Temporary substation on the job in the Cartersville transmission line rebuild.

The company had a “wreck-and-rebuild” job on an older transmission line between the Bremo Power Station and a substation in Cartersville. Typically, says Lamb, a temporary transmission line would be constructed to carry load to customers while the old line was being rebuilt. In this particular case, a five-mile section had poor access.

Besides saving the $4 million expense of stringing a temporary line, says Lamb, the company was able to conduct a “proof of concept.” Workers proceeded slowly and deliberately over four months in order to work out set-up processes and develop checklists.

“We accomplished a lot of things with this one installation,” Lamb says. “If we have an unplanned situation in the future, we could hopefully make it within five to seven days.”

Nationally, the electric grid is aging. Most transformers in the United States were installed between 1950 and 1970, and have far exceeded their expected 40-year life span. U.S. utilities, some fear, may be forced to contend with an increasing number of breakdowns. Thus the grid is growing more fragile even as the threat of sabotage, cyber attacks and natural disaster looms ever larger.

While Dominion says that it has been proactively replacing older transformers, substation equipment, and transmission lines in order to improve reliability, the mobile transmission equipment gives it an added safeguard against an extended outage.

“The installation of the mobile transmission substation in Cartersville was a first in North America, and the equipment operated as designed,” says Lamb. “Dominion will definitely be better equipped and prepared in the future to respond to unplanned events.”

There are currently no comments highlighted.

8 responses to “A Substation in Time Saves Nine

  1. Apparently don’t have that capability down at Hatteras and Ocracoke which just lost all power.. a few days ago.. ironically from bridge construction! You’d think they’d know where NOT to drill these days!

    at any rate – having a resilient, redundant grid also plays into the solar/wind conundrum… if you have a grid that can “dynamically mend” in response to failures.. you probably are able to do that also for the variability of wind/solar so it’s a win-win!

    I bet Hatteras and Ocracoke businesses and rental properties are gonna be talking about how much money it would have cost to have “backup” versus money lost when not!

  2. I handled a lot of cable cuts in my day when I was in in-house lawyer for the Telephone Company. I remember one case where the Power Company wanted compensation for cutting one of its cables. Before we worked in the area, we had Miss Utility mark the power line. But it was cut anyway.

    After investigating, it was determined that the contractor laying the power cable had extra cable. So instead of cutting it to length and then connecting it, the contractor made a giant loop of the excess cable and then connected it. The loop extended well beyond the place where the line was marked. We didn’t pay that one. It’s very important to put cables exactly where they are supposed to be and then to call before one digs.

  3. It sounds like Dominion is being very cautious and proactive with that equipment. Nice … but before they rebuild the old grid substations they need to think more about what our changing grid will look like. Where will microgrids be a better answer? Where will corporate onsite renewables change the demand picture? Where is that ACEEE 23% decline in demand by 2030 from efficient buildings located? Where and when will offshore wind, with it’s enormous generation potential, come ashore?

    • CA&W. Ditto on the offshore wind. Would that someone would figure out how to use the ocean’s waves.

      I still struggle with the idea that we will be able to retrofit a large number of buildings to achieve the projected decline in demand. Big new buildings and government building remodeling will certainly provide energy savings. But where does the money come from to do the rest of the buildings and the many homes – most of which are owned or rented by people who don’t have money to burn?

      Fairfax County indicates a good two-thirds of its office buildings are functionally obsolete. Some will be repurposed. Some will be torn down and replaced by more energy-efficient buildings. But most won’t. I don’t see anyone spending a dime to make them energy efficient. And then toss in the many homes, townhouses and apartments. Unless and until we have several years of rising personal incomes, I just don’t see most people taking on significant capital expenses that won’t produce savings that outweigh the higher expenses to pay for the retrofitting of buildings.

      • re: ” But where does the money come from to do the rest of the buildings and the many homes – most of which are owned or rented by people who don’t have money to burn?”

        for many – if they can recoup an outlay in a few months or year or two – they will… but also.. replacement appliances.. new heat pumps, etc.. are more efficient… new thermostats… will easily not heat or cool an empty house and get it comfortable with a simple command from a smart phone from someone an hour before heading home.

        The way technology is moving these days….it’s inevitable it will reduce consumption… certainly in new construction but even companies like Walmart have 20% and higher goals to reduce.

        I’m not be surprised at all that on a per capita basis – we cut by 20% in a decade or so…

        take a look at this:

        Evidence of a Decline in Electricity Use by U.S. Households


  4. I guess folks saw this also:

    Report: Plug being pulled on Plant Vogtle’s nuke twin in South Carolina

    Russell Grantham The Atlanta Journal-Constitution
    2:23 p.m Monday, July 31, 2017

    n a press release, one of the partners in the project, SCE&G, said Monday that rising costs of the $14 billion V.C. Summer nuclear station expansion project, falling demand for electricity, construction delays and the bankruptcy of a key contractor were reasons behind the decision, according to The State newspaper in Columbia, S.C.

    The Vogtle project to add two new nuclear reactors at a Georgia Power plant near Augusta faces a similar set of challenges.

    can’t be good for NA3

  5. Corporate decisions are driving the efficient buildings and on-site generation. Commercial PACE loans are very useful as the loan payments plus new reduced utility bill is less than the old utility bills. See examples at PACENow.org

    AND … here is a corporate example … JP Morgan Chase has set the goal of being completely dependent on renewable energy by 2020. The bank said it will install renewable energy technology across buildings and branch offices; sign agreements with renewable energy projects; and reduce energy consumption. It will develop onsite solar generation for up to 1,400 bank-owed retail and 40 commercial buildings globally and install fuel cell technology at some sites.

    BUT … The 51 largest electric utilities in the country were recently evaluated on their overall success in reducing energy use. On every measure, Dominion received failing scores, ending up with a dreadful 5.5 out of a possible 50 points.

  6. Re: ” JP Morgan Chase has set the goal of being completely dependent on renewable energy by 2020. ”

    I don’t want to be a grinch but I’m probably asking a question that many skeptics and even just ordinary folks might ask – and that is how can you you say you are using only renewable energy at night?

    I understand that “renewable energy” is being marketed and that you can buy enough of it to say that your total amount of power bought – covers your demand – and is bought as renewable.

    but realistically what does that really mean if the grid power being used by J.P. Morgan at night – is being generated by baseload from coal/nuke/gas unless it’s coming solely from wind or batteries.


    So is this some kind of “offset” idea based on the premise that if enough solar/wind being generated and used… is actually offsetting the burning of fossil fuels and that essentially becomes a “credit” but it sorta feels like if you’re using it during the day and also claiming it’ a credit – it’s double counting unless the user of it during the day is not counting it as renewable.. and instead is in effect still using nuke/coal/gas and allowing the purchaser of the credit to claim it as a renewable.

    How do you keep the solar from being counted twice? Is it a separate market – and once all of it has been bought – there are no more available tranches until more solar is added to the grid?

    Is that what Amazon and others are doing? They building enough solar that in theory covers their 24/7 demand but at night they’re using grid power that’s coming from coal/nuke/gas and they’re selling the excess solar – during the day – essentially as credits to folks like J.P. Morgan?

    If you build more solar than the grid can accommodate during the day what does that mean in terms of renewable credits than can be purchased to offset nighttime? Does it mean that the amount of renewable energy that can be bought either direct or as offset credits is capped at how much renewable energy the grid can actually accommodate?

    The answer to that question is important because it has implications – in terms of how much solar can actually be built…. if it cannot be used by the grid during the day – nor sold as a renewable credit ..because it’ really not feeding into the grid …

    And that point – companies seeking to say they are operating 100% off of renewable power – won’t be able to buy sufficient credits… I would think.

    i.e. – once the grid is saturated with solar during the day – that’s it.

    the only other way to do it would be to build solar on site and use solar-charged batteries at night… I’m assuming at this point there are few if any companies doing this because of the high cost of batteries…

    and if this was a viable option – then there would be no need to buy offset credits… and any property could run stand-alone… including entire islands.

Leave a Reply