Emerging technologies and the electric grid

A task force examining the deployment of emerging technologies across the North American electric grid has identified three imperatives necessary to ensure the continued reliability and efficiency of the bulk electricity system, relating to: renewable supply and integration; greater situational awareness; and controlling an increasingly distributed energy system, with increased deployment of distributed energy resources.

The 39-page report, “Emerging Technologies: How ISOs and RTOs can create a more nimble, robust electricity system,” was published on March 16, 2017, by a group of nine Independent System Operators (ISO) and Regional Transmission Organizations (RTO) known collectively as the ISO/RTO Council (IRC).

With respect to integrating renewable resources, the IRC noted that it "[s]upports policies and positions recognizing the electricity system’s ability to accommodate large amounts of renewables and realizing their growing potential."  While remaining "agnostic to specific technologies that may faciiltate renewable integration", IRC supports policies that accommodate emerging renewable integration technologies, while "avoiding early technological lock-in."

With respect to situational awareness, the IRC notes the lack of available data on the penetration of distributed energy resources, but that a lack of data or its sharing should not limit grid operators' understanding of what's happening on the grid.  IRC suggests the development of a general operational data framework, "where increasingly comprehensive operational data from the distribution system is provided as DER penetrations reach different thresholds."

The report also notes, "Because of emerging technologies, North America’s electricity systems are moving toward a more distributed arrangement." In 2016, the Federal Energy Regulatory Commission issued a Notice of Proposed Rulemaking in which it proposed rule changes "to remove barriers to to the participation of electric storage resources and distributed energy resource aggregations" in organized wholesale electric markets.  Recognizing that such a rule change could set a framework for future DER growth, the IRC calls for continued coordination, data sharing, and flexibility.

FERC Order 827 and reactive power

Federal energy regulators have issued a final rule requiring all newly interconnecting non-synchronous generators to provide reactive power, which supports the reliability of the electric grid.  The rule adopted by the Federal Energy Regulatory Commission in Order No. 827 primarily affects wind generators, who have previously been exempt, and some solar projects.

Reactive power -- and generators capable of supplying or consuming it -- play an important role in controlling system voltage for efficient and reliable operation of an alternating current transmission system.  Previously, as a condition of interconnection under the FERC's pro forma Large Generator Interconnection Agreement and Small Generator Interconnection Agreement, most generators have been required “to maintain a composite power delivery at continuous rated power output at the Point of Interconnection at a power factor within the range of 0.95 leading to 0.95 lagging.”

But historically, the costs to design and build a wind generator that could provide this kind of reactive power were high.  In recognition that requiring wind generators to provide reactive power could have created an obstacle to the development of wind generation, the Commission previously exempted wind generators from the general requirement to provide reactive power, absent a study finding that the provision of reactive power is necessary to ensure safety or reliability.

But in 2014, a FERC staff report found that the cost of providing reactive power no longer presents an obstacle to the development of wind generation.  So-called Type III and Type IV inverter-based turbines now offer inherent reactive power capabilities.  As described in Order No. 827, "The resulting decline in the cost to wind generators of providing reactive power renders the current absolute exemptions unjust, unreasonable, and unduly discriminatory and preferential."  The Commission also noted that integrating increasing amounts of wind increases the potential that some systems will need more reactive power.

Acting under Section 206 of the Federal Power Act, on June 16, 2016, the Commission found "that wind generators should not have an exemption from the reactive power requirement which is unavailable to other generators." At the same time, the Commission recognized technical differences that would add costs if non-synchronous generators were required to provide reactive power at the Point of Interconnection -- and that these "added costs will ultimately be borne by customers, whether through reactive power payments in regions that compensate for reactive power capability, or through elevated prices for capacity or energy in regions that do not compensate for reactive power capability."

It thus adopted reactive power requirements for newly interconnecting non-synchronous generators, but let non-synchronous generators provide dynamic reactive power at the high-side of the generator substation, as opposed to the Point of Interconnection.

The Commission described its expectation that non-synchronous generators may meet the dynamic reactive power requirement by utilizing a combination of the inherent dynamic reactive power capability of the inverter, dynamic reactive power devices (e.g., Static VAR Compensators), and static reactive power devices (e.g., capacitors) to make up for losses.

The Final Rule will become effective 90 days after its publication in the Federal Register.  Its requirements will apply to all newly interconnecting non-synchronous generators that have not yet executed a Facilities Study Agreement as of the rule's effective date.

August 5, 2010 - Patriot Place gets solar power; integrating wind into the grid

 
 Solar power in action: making wind, pushing sails past Ram Island Light, Boothbay Harbor, Maine.

Several large utilities including Duke Energy Corp. have reported significantly increased power sales for the second quarter of 2010, particularly from industrial customers.  Duke now projects that 2010 power sales will rise 2%.  At its midwestern operating companies, Duke noted 20% growth in industrial power sales.

Here's a short letter to the editor of the Lewiston Sun Journal about old swimming holes now gone, including the impoundments behind older mill dams like the Barker Mill Dam on the Little Androscoggin River.

Add another high-profile place to the list of large businesses adding solar power: Patriot Place, the shopping mall adjoining the New England Patriots' Gillette Stadium, has installed a 525 kW solar array.  They turned to Constellation Energy for the installation, but the solar photovoltaic panels themselves were manufactured by Evergreen Solar of Massachusetts.

Wind turbine prices are flat, averaging about $1.37 million per megawatt of capacity according to a survey by Bloomberg New Energy Finance.  (Note that this is just the turbine price; towers, transmission and installation are all in addition to the turbine price.)  Turbine pricing is down about 15% from its peak in 2008, likely due to a mix of factors including new technology and increased production capacity, but also some decreased demand compared to the initial fervor.

Meanwhile, people continue to solve the problem of how to integrate wind into the grid.  Energy storage is one major approach.  Xcel Energy has issued a report on its experiments with massive 1 megawatt batteries to smooth out voltage and current from wind farms.  Xcel's project in Minnesota is promoted as America's first direct wind-energy-storage project.