This Ain’t Your Father’s Electric Grid

This chart shows the dramatic drop in Dominion’s solar energy output during the recent solar eclipse.

Is Thomas Edison’s electric grid ready for the future? In some ways yes, and in other ways not yet. So says Kevin Curtis, vice president-technical solutions for Dominion Energy Virginia.

The challenges of integrating renewable energy sources and protecting against cyber-threats have created the need for a smarter, modernized grid, Curtis said today in a Northern Virginia Technology Council forum on the topic of powering Northern Virginia’s high-tech economy.

“Grid modernization means a smarter grid, a self-healing grid, with fewer disruptions and fewer customers impacted,” Curtis said. The reliability and quality of electric service is especially critical to technology companies, which not only need to maintain uninterruptible service but keep voltage and electric frequency within a tight range.

In 2015 Dominion had only one megawatt of solar power on its system. Today the number is 744 megawatts online or under development, and the company expects to add 5,000 megawatts over the next couple of decades. The transmission grid of high-voltage electric lines is designed for electricity to flow bidirectionally, which means it can readily accommodate large utility-scale solar farms. But the distribution system of lower-voltage lines that deliver electricity to homes and businesses was designed for one-way electricity flow. Dominion has taken a go-slow approach to rooftop and other small-scale solar as it has learned more about their impact on the distribution system.

Rapid variations in solar output can create fluctuations in voltage and frequency that can damage customers’ machinery and equipment, said Curtis. “It’s not a deal breaker, but we have to be sure we understand the interactions.”

During the solar eclipse, output dropped to 10% of normal solar rating and then jumped back to normal, all within a few minutes. Power companies had to keep supply and load in balance on local circuits or risk adverse consequences. Said Curtis: “It’s an operational challenge.”

A modern grid provides more real-time information of what’s happening on the system, more intelligence about voltage and frequency, and the ability to predict problems before they occur. A smart grid also provides customers more information and control over their energy usage.

While Curtis spoke about the necessity of building a smarter grid, he did not say what upgrades Dominion has planned for its system or how much they might cost.

The other challenge is grid security, both physical and cyber. The “marquis moment” for Dominion came in April 2013 when unidentified saboteurs launched a coordinated attack on a Pacific Gas & Electric substation serving Silicon Valley, knocking it out of service and causing PG&E to reroute flows of electricity.

“The very next day, Dominion began to rethink our system,” said Curtis. Everyone from terrorists to hostile nation states are probing the grid. “We know it’s happening. It’s on the forefront of our minds. We have a team of people at Dominion specifically focused on these issues.”

There is no one approach to securing the grid. Dominion is assessing its vulnerabilities, hardening its facilities, and bolstering surveillance of the system, he said. “We recently completed a brand-new, state-of-the-art transmission center north of Richmond that is protected against electro-magnetic pulses and has armed protection,” he said.

State Secretary of Technology Karen Jackson said that the demand for reliable service is “at an all-time high” and is a growing concern in the state’s effort to recruit data centers. Two key infrastructure considerations for data centers are bandwidth and electricity. “We have to have the infrastructure that can keep pace, while also being respectful to the environment.”

Conversations like the one taking place between Dominion and the Northern Virginia technology community are vitally important, she said.

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8 responses to “This Ain’t Your Father’s Electric Grid”

  1. Reed Fawell 3rd Avatar
    Reed Fawell 3rd

    I am relieved to see this kind of thinking. We are in for a very long time of trial and error, and learning and correction, if we are to get this right. This means we have to keep our options open for a long as possible to insure that we can climb back down any particular limb, and thus avoid great loss, wastage, unfairness or harm to others. Unfortunately, history shows many undue pressures out there to grab big utility wind and solar farms with all their attendant risks, losing all prudence for short term gain, fad or simple hubris. Like Germany has done, for instance.

  2. Ivy Main Avatar

    The solar eclipse was predicted, therefore grid operators made up for the drop in solar output by calling on other forms of generation. Fossil fuel and nuclear generating plants are taken offline routinely for maintenance. Their generating profiles drop to zero, too. How is this a story?

    1. Ivy, you’re absolutely right that grid operators could predict the eclipse, and I don’t think anyone experienced any difficulty as a result. Curtis was just using an extreme example to show the variability of solar output. He also presented slides showing output under sunny skies and output during cloudy conditions, as seen here:

  3. Jim it’s probably George Westinghouse’s grid, not Thomas Edison’s. Edison was a DC (direct current) advocate and said AC (alternating current) was far too dangerous. Edison suggested we not say the word “electrocuted” instead the term should be “Westinghoused”.

  4. As I understand it, Dominion’s grid services subsidiary is a capable organization. But there are some misleading points here.

    As Ivy related, unplanned outages of large conventional generating units are far more severe events for grid operators to deal with than predictable variations in solar output.

    The article seems to indicate that much of the need for grid improvements is a result of solar development. A modern grid, with a two-way flow of energy and information, is necessary regardless of the amount of solar penetration. Dominion has added a significant penalty to solar installations as a “grid integration” cost that does not apply to conventional units. This skews fair economic comparisons between various sources of generation. An accurate value of solar tariff would remove this artificial penalty.

    Recent studies in California have shown that renewable energy “can sustain system reliability as effectively and more efficiently than a natural gas plant.”

    Grid operators were surprised “that inverter-based resources could respond so accurately.” The California study showed that solar facilities “can reliably provide frequency control, voltage control, ramping capability, which are three essential reliability services.”

    It is appropriate that Dominion evaluate the requirements for a modern grid. But I suspect that Dominion “has taken a go-slow approach to rooftop and other small-scale solar” partly because these installations currently reduce Dominion’s revenue.

    This is a conundrum for modern utilities. What is good for the customer today, is not necessarily good for the utility. Rather than drag our feet and blame the customers for doing what makes sense to them, we should alter the way we pay our utilities so that they can make money serving the customer better. Allowing Dominion to take take a slower approach of modernizing our grid, will not serve the interests of the state.

    Dominion has a capable organization that can help take us into the 21st century. Let’s line up a performance-based regulatory scheme that encourages them to do that, as long as it serves the needs of their customers too.

    1. TooManyTaxes Avatar

      So why not come with a regulatory plan that protects residential and small business customers while allowing Dominion, willing big customers and other energy interests to experiment? A rate freeze without the open-ended fuel adjustment provisions that have effectively eaten the rate freeze. Or freeze rates and allow Dominion to pass on half of its cost increases. If we had an active consumer advocate, we might be able to come up with something that works and is fair.

      I don’t trust Dominion. They don’t even trim trees regularly in Fairfax County and have too damn many outages. I don’t trust the Chambers of Commerce because, in Virginia, they are generally owned and operated by the real estate development industry. I don’t trust the environmental groups because their cause is more important than people and no one, including the MSM, has the stones to challenge their arguments. All arguments and assertions should be tested.

      As far as Thomas Edison is concerned, I seem to recall he effectively invented the electric chair to defeat Westinghouse.

      1. TMT,

        Declines in fuel costs have added to the profits that Dominion has accumulated as a result of the rate freeze. As the company shifted to a higher portion of gas-fired generation, we experienced historically low gas prices (in inflation adjusted terms). The prices were well below what was probably baked into the base rates. An annual fuel factor adjustment is made to catch up with year to year adjustments, but I don’t think there is an opportunity to make fuel cost adjustments in the base rate, except in the biennial reviews, which have been suspended. Dominion benefited greatly from the timing and the rate freeze.

  5. CleanAir&Water Avatar

    “Dominion has taken a go-slow approach to rooftop and other small-scale solar as it has learned more about their impact on the distribution system.” “It’s not a deal breaker,” … “It’s an operational challenge.”

    Jim is right to point out … “While Curtis spoke about the necessity of building a smarter grid, he did not say what upgrades Dominion has planned for its system or how much they might cost” … Dominion does not have to reinvent the wheel here. Last month, Scottish wind turbines provided 846,942 megawatt hours of electricity to the National Grid, enough to supply the power needs of 2.25 million, or 93 percent of Scottish households, according to WWF Scotland.

    WSJ reports … In partnership with Tesla Energy, Green Mountain Power is offering 2,000 of its customers the opportunity to have a Tesla Powerwall in their home for $15 a month. The 13.5 kilowatt-hour batteries retail for $5,500, but the utility can afford to put them in homes because they help the company save on other grid infrastructure, says Mary Powell, GMP’s chief executive and president.

    RMI says … “We also know that high penetrations of renewables can be managed reliably … wind energy in Texas often provides more than 30 percent or even 40 percent of the state’s daily power needs throughout the entire day. “

    California Gov. Jerry Brown (D) on Wednesday signed a bill directing utilities to plan carbon-free alternatives to gas generation for meeting peak demand. Now that it is law, utilities will have to alter their IRP processes to evaluate “the role of existing renewable generation, grid operational efficiencies, energy storage, and distributed energy resources, including energy efficiency” to meet the hours of peak demand.

    Which brings us to the fact … Regulations are key to driving that change. Tom has said the same thing often. Without our regulators on the job how can we see progress?

    Dominion should stop relying on long-term large capital investments because the future of demand is in question. Demand projections are just about impossible now for 10 year ahead. Instead, DERs and renewables offer small, low-risk, low-cost resources that are more flexible than the large, high-risk, and expensive projects typical of traditional infrastructure investment.

    Such projects can be sited, permitted, and built more rapidly than traditional power plants or grid upgrades, creating projects that are right-sized to meet near-term needs in near real-time. Doing so removes much of the risk and uncertainty inherent in the long-term forecasts required to plan traditional infrastructure and building pipelines based on a ‘need’ grounded only in hope for profits.

    Projects like the ones above would show that Dominion is actually looking to a different future.

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