BENEfits of SolidGround™

Cover Photo:  SolidGround™ protecting a 300 MVA 345kV / 138kV Transformer


Tested & Proven Technology

    Click SolidGround™ Brochure above to Download

    Click SolidGround™ Brochure above to Download

  • SolidGround™ was extensively studied and modeled by the University of Manitoba
  • SolidGround™ has been fully fault tested at KEMA High Current and Voltage Laboratories in Pennsylvania proving the robustness of design. 
  • SolidGround™ was the subject of a NERC sponsored study performed by the Electric Power Research Institute (EPRI) in 2014 which concluded that neutral blocking devices have no unintended consequences when introduced into a power grid network.
  • SolidGround™ was tested on the live grid at Idaho National Laboratory by the U.S. Department of Defense (DOD) and the U.S. Defense Threat Reduction Agency (DTRA) and met all performance requirements. 
  • No system resonance has been calculated or reported and systems relays operated correctly without requiring changes.

SolidGround™ is currently in operation on the North American power grid and performing as designed.


EMP and Solar Storms

A Nuclear EMP event results in three pulses of energy, named E1, E2 and E3.  The E1 pulse is a high intensity RF energy typically in the microwave frequency band which destroys or disables electronic controls that contain computer chips.  The E2 pulse is often compared to a lightning strike.  The E3 pulse has a slow time variation which results in quasi-DC currents "hundreds to thousands of amperes in long conducting lines...that damage components of the electric grid itself as well as powered systems". -Dr. Baker, Principal Staff, EMP Commission

Solar Storms produce Geomagnetic Induced Current (GIC), a quasi-DC current similar to E3.  Within the past 25 years, numerous solar storms have damaged utility transformers and have caused blackouts to regional power grids, resulting in huge economic loss.  A severe solar storm, similar to those recorded in 1859 (before the U.S. power grid existed) and in 1921, could darken large portions of the U.S. for an extended period, and create societal chaos.

GICs from even moderate solar storms find their way into power grids and cause problems.  A recent insurance study on North America by C.J. Schrijver, R. Dobbins, W. Murtaugh, and S.M. Petrinic in the Space Weather Journal, 2014 states "For an average year, the economic impact of power quality variation related to elevated geomagnetic activity may be a few percent of the total impact, or several billion dollars annually."


EMP E3 Pulse

The threat and consequences of a Nuclear EMP attack have been studied since the 1950's (extensive reports published) and have included two formal U.S. Congressional EMP Commissions (reports published in 2004 and 2008).

2008 EMP Commission Report States:

"The E3 pulse is similar in a great many respects to geomagnetic effects induced by solar storms.  Solar Storms and their impacts on electrical systems with long lines have been thoroughly evaluated and are known to cause serious damage to electrical system components at much lower levels than the reasonable possible E3 impact."

"System wide ground-induced currents in the transmission grid can by themselves cause system collapse.  They did so in March 1989 in Quebec.  At the levels expected in an E3 event, collapse would be much more likely and widespread."

"Commission analyzed the impact of a 100-year solar storm (similar to E3 from EMP) and discovered a very high consequence vulnerability of the power grid.  Steps taken to mitigate the E3 threat also would simultaneously mitigate this threat from the natural environment."

SolidGround™ Protects the Power Grid from both Solar Storms and Nuclear EMP E3:

  • SolidGround™ components are shielded and designed to operate through all three EMP pulses: E1, E2 and E3.
  • EMP.Alert™ detects an EMP event in milliseconds and can trigger SolidGround™ into protective mode well before the E3 pulse arrives.
  • SolidGround™ can be constructed with modular capacitor bank add-ons to achieve protection not only from any size GIC but also very high currents induced by Nuclear EMP E3 fields.  Additional modular add-ons can be added at any time for longer lines or extremely high anticipated E3 fields to meet customer future needs.

Additional Benefits of SolidGround™


Increases the Stability and Reliability of the Grid

  • Protects against power system voltage collapse or outages caused by Solar Storms / EMP E3
  • Protects the most critical, costly and long lead items of a Power Grid: High Voltage (HV) / Extra High Voltage (EHV) Transformers, Generators and Circuit Breakers against the effects of Nuclear EMP E3 and Solar Storms. 

Reduces or eliminates damaging harmonics

  • Reduces or eliminates transformer vibration and excess current (VAR consumption)
  • Reduces misoperation of relays and protective equipment due to harmonics
  • Reduces Stress on HV and EHV transformers and other power system components by decreasing transformer half-cycle saturation which can cause vibration and heating of equipment.  If severe, possible thermal damage to equipment can occur.
  • Reduces transformer noise when under stress
  • Enhances the robustness of aging or vulnerable transformers by blocking DC current.

Reduces utility costs

  • Reduces/eliminates added costs of "Uneconomic Dispatch" when a Solar Storm is predicted
  • Reduces GIC induced reactive power (VAR) Consumption
  • Insurance industry may be headed towards reduced insurance premiums when there is protection of customer assets
  • Simplifies expensive and complex utility response procedures to solar storms which may not be effective.  SolidGround™ is always ready to provide automatic and immediate protection when needed

Features Overview


Multiple, redundant, parallel, individually fused capacitors, all systems fault protected

Robust design and highly fail safe

  • Major components are proven, industry standard, the highest quality, provided by ABB and Schweitzer
  • Components are designed to take multiple faults with no cool down period required
  • SolidGround™ always provides a hard wired and effective AC ground through capacitors
  • Fully automatic with little to no operator action required
  • Scalable to protect the entire grid against a severe Carrington-level geomagnetic disturbance (GMD) and Nuclear EMP E3.

Controls built by Schweitzer Engineering Laboratories (SEL)

Schweitzer control electronics

  • Continuously monitors for DC currents, GIC induced harmonics and EMP E1 as desired.
  • Settable thresholds allow for site-specific customization
  • Communicates with SCADA Systems
  • Allows for alarms, warnings, messages to other systems or sites and logging of GIC activity
  • Allows manual control of unit for specific purposes such as testing, if desired.
  • Shielding protection can be provided for EMP E1 and IEMI as desired.

Photo of DuraGap™ enclosure installed on SolidGround™

DuraGap™ overvoltage protection

  • DuraGap™ is a robust patented spark gap (3 parallel gaps) specifically designed because there was nothing available on the market capable of handling the unique combination of voltage and amperage required by utilities.
  • DuraGap™ provides over-voltage protection for repeated high fault (20kA) currents
  • In KEMA Lab tests DuraGap™ easily carried 20 faults with 10kV breakdown and 20kA.  No degradation was found.

SolidGround™ is the most effective solution to protect the electric power grid from both Nuclear EMP E3 and Solar Storms.