Navigant Research Blog

Data Centers Morphing Into Virtual Power Plants

— February 12, 2013

Source: ABBWhat is a “virtual power plant?” The term means different things to different people in different parts of the world.  Pike Research has come up with its own definition: A system that relies upon software to remotely and automatically dispatch and optimize generation, demand-side, or storage resources (including PEVs and bi-directional inverters) in a single, secure web-connected platform.

At their core, VPPs tap existing grid networks to tailor electricity supply and demand services for a customer, utility, or grid operator.  Without any large-scale fundamental infrastructure upgrades, VPPs can stretch supplies from existing generators and utility demand reduction programs.

The latest VPP model to emerge is based not on geographic proximity – typically the top consideration – but rather on enterprise ownership of global operations.  Ironically enough, the farther away each facility linked in the VPP, the better!  Companies such as PowerAssure are investigating ways for companies that use large global data center operations, such as Apple and Google, to create enterprise VPPs that span the globe, whereby data centers shut down operations and shift load from the regions of the world in daylight to the nighttime half of the globe, where power is cheaper.  The technology to carry out this level of global energy arbitrage – known as “following the moon” – is nearly here (though some engineers may disagree). “Data centers can modulate their IT loads based on external events, such as the price of power, and in the process, save money and get paid for providing demand response (DR) services,” Peter Maltbaek, vice president of worldwide sales for PowerAssure, told me.

Changing Models and Mindsets

The U.S. Environmental Protection Agency (EPA) recently revised rules governing limits imposed upon use of diesel generators that should help increase the availability of DR throughout the United States.  The chief challenge for global enterprise VPPs comes on similar regulatory restraints as well as the accounting end of such transactions.  Of course, if large numbers of large energy users employed this strategy, it could wreak havoc with local grid stability instead of enhancing reliability.  How national and regional regulators would respond to such a business model, based largely on financial flows instead of engineering smarts, is unclear.

Another challenge is changing the mindset of data center owners.  “They need 100% availability and are leery of anyone fooling around with their power supply, especially since it is only typically 3% of total costs,” added Maltbaek.

Lawrence Berkeley National Laboratories (LBNL) released a study last year that looked at data centers and their potential for DR.  ABB, which has invested in PowerAssure and has its own Decathlon DCIM VPP offering for data centers, has already installed a 1 megawatt (MW) DC microgrid at a data center in Zurich, Switzerland providing DR through use of its emergency generators; this system is currently being expanded to 10 MW, will later go to 30 MW, and will then be aggregated with three other data centers in the region.

In Germany, meanwhile, Siemens claims that recent regulatory reforms will allow it to boost its supply-side VPP capacity to 3,000 MW by 2018.  Last year, the company announced that it would increase the capacity of its VPP from less than 10 MW to 200 MW by 2015.  The company says that Germany has enough spare capacity on its transmission lines to create VPPs that span the entire country.


Lessons from the Blackout Bowl

— February 4, 2013

Source: Energy.govIt’s safe to say that the electrical systems supervisor is not the person that Superdome officials wanted the world’s media to be talking about the morning after the Super Bowl.  For 34 dimly lit minutes, starting early in the third quarter, that person’s competence was one of the many things that the more than 1 billion people watching the game were discussing.

There’s a lot we don’t know about exactly what happened when the lights went out on the Super Bowl.  But here’s what we do know:

Not all the lights went out: One-third of the lights stayed on throughout that excruciating half hour.  That probably means that the uninterruptable power supply system worked as planned.  The only problem was that the UPS system was sized to one-third the necessary power needs of the stadium.

The lights weren’t the only things going out: The CBS announcers lost power, as apparently did the top-level cameras and the coaches’ communications systems.  This points to a failure in wiring the building’s critical circuits.  By far the most important thing to keep going in the case of an emergency (after emergency lighting and the PA system, both of which worked) is the power to the television operations.  Television is what pays everyone’s bills, so that should have priority over other systems.  It did not.  Likewise, the fact that one team’s communications systems continued to work (the 49ers) and the other’s didn’t (the Ravens), showed that someone didn’t think very clearly when designing the critical circuit design.

LEDs still shone: If you looked carefully at the scenes of the blackened sections of the stadium seating, you could see that the emergency stair lights were all still lit.  Likewise, the exterior colored lighting that bathes the outside walls of the stadium in light was still working.  That’s because it’s made up of LEDs, which consume a fraction of a percentage of the power required by the sodium high intensity discharge (HID) lamps used for the rest of the stadium lighting.  Additionally, the sodium HIDs, once they went out, took another 20 minutes to regain their full luminosity.  LEDs, on the other hand, require no warm-up time and sip so little electricity that managing the current for them is a much less complex task.

Engineers and Repairmen

Based on this knowledge, here are three important lessons learned from the power management debacle that was Super Bowl XLVII:

  • Right-sizing a UPS backup microgrid is about more than just installing a bunch of generators.  The art of designing a backup microgrid is about balancing the maximum number of diesel gensets with the minimal amount of load.  Physical space for backup gensets is almost always limited (especially in a flood plain like New Orleans, where generators have to be placed – at a minimum – on the second floor).  Thus, keeping the blackout from happening was more of a failure of critical circuit design than of generator management.
  • Energy efficiency counts more than backup power in times of emergency.  The failure of the sodium HID lights and the long warm-up time they require would have been solved by energy efficient LED lights, which also would have reduced the load on the UPS system.
  • Electrical design engineers are always more valuable than electric repairmen.  Designing the critical circuits to be prioritized during a power failure is a job worth doing right, as we saw on Sunday evening.  The designers of the Superdome’s UPS circuitry got some things very right: the success of the emergency lighting system kept the crowd from panicking.  But the problems with the broadcasting and team communications systems showed that not everything was so well-planned.

Why Military Microgrids’ Influence Exceeds Their Market Share

— January 15, 2013

Source: WikipediaGlaring evidence of the electrical grid’s vulnerability to severe storms on the East Coast has increased interest in microgrids, which can provide continuous power in the event of a utility service blackout.  As documented in Pike Research’s recent report, Military Microgrids, the U.S. military, the largest consumer of energy in the world, is one of the strongest proponents of this technology.

The U.S. Department of Defense (DOD) microgrid that carries the greatest implications for the larger commercial market is located at Twentynine Palms, the large U.S. Marine Corps base, near Joshua Tree National Park in Southern California.  Some 10,000 Marines train here at a site that stretches over 932 square miles, an area larger than the state of Connecticut.  With a capacity of approximately 13 megawatts (MW), and a generation portfolio featuring solar photovoltaics (PV), combined heat and power (CHP), and a new advanced metal halide energy storage system, this stationary base microgrid is clearly the showcase for General Electric’s microgrid solution for DOD.

The most cutting edge microgrid testing program at Twentynine Palms, known as “ExFOB,” (Experimental Forward Operating Bases), is aimed at overseas installations.  While the focus of large companies such as GE to date has been on domestic base military microgrids, the most radical innovations could occur overseas, where DOD operates approximately 600 FOBs, the majority of which are not connected with reliable power grids.

The 3rd Battalion, 5th Marine Regiment was chosen as the unit that would conduct the demonstration and testing of new renewable and efficiency technologies at ExFOB.  The deserts of Southern California feature an environment in the United States that resembles that of Afghanistan, where the battalion would eventually deploy in August of 2011.  The following three technologies were integrated into microgrid tests:

Solar Power Shade: The Military Solar Power Shade Shelter provides up to 1 kW of continuous solar power to low-power draw items.  It also provides shade from the sun, reducing solar heat loads from 80% to 90%.

Ground Renewable Expeditionary Energy System (GREENS): These solar PV-based systems are capable of continuous power, or 1 kW of peak power, designed to be scalable and adaptable for missions that do not require a full base-scale power source or energy storage.

Light-Emitting Diodes (LEDs): Lighting kits provide continuous tent lighting over a 20-day period in temperatures from 85 to 112 degrees Fahrenheit.  This saves a significant amount of energy and works well with renewable energy sources.  The durable lighting system can be set up by two Marines in less than 5 minutes.

A handful of these hybrid solar PV/battery/diesel generator systems were first deployed in July 2011.  They have proven so valuable that two small patrols in Afghanistan have been operating completely on renewable energy.  Another small base has reduced fuel use by 90%.  So far, over 400 portable Solar Portable Alternative Communication Energy Systems (SPACES) have already been deployed in Afghanistan, following testing and validation at ExFOB.

The DOD has played a consistent role in commercializing new technologies that provide tremendous social benefits in the civilian realm.  The microgrid may be another instance where the DOD plays an incubator and market maker role.  The developing world could apply a new model of grid infrastructure, as microgrids deployed initially by DOD are then adopted for non-military village power or industrial mine remote microgrid applications.  The opportunity to help develop these microgrids has attracted a number of powerful technology companies beyond GE, including Lockheed Martin, Honeywell, Boeing, and Eaton.


In China, Wind Power Fuels Microgrids

— December 6, 2012

Wind energy in China has been expanding at an incredible rate, and the Chinese government hopes to speed up this deployment in the future.  Currently, China has approximately 62.4 gigawatts (GW) of wind energy installed, mostly in the remote northern and western regions of the country.  Transmission infrastructure, however, has not kept pace; up to 20% of the power generated is wasted because the wind farms are not connected to the grid.

Microgrids could be the solution, or at least an interim step, to integrating this burgeoning generation capacity.  By definition, microgrids incorporate distributed generation resources and have the ability to isolate, or “island,” themselves from the greater electric grid.  Deploying microgrids near the sites of non-grid connected wind power would have three main benefits:

First, microgrids utilizing the wind generation would provide the surrounding communities with a more reliable source of electricity.

Second, since microgrids have their own generation resources, they draw less power from the electric grid than regular loads.  This means that capital investments in transmission infrastructure would be reduced, since less power would need to flow into the microgrid, and already strained utility budgets would be eased.  For example, a significant amount of wind capacity exists in Inner Mongolia, but the region has a relatively small load compared to the more urbanized parts of China.  The regional utility, Inner Mongolia Grid, lacks the funds to build sufficient transmission capacity to the rest of the country.  Using that power to create local microgrids would benefit both the region and the power producers.

The third benefit is more subtle.  Microgrids enabled with storage components (e.g., batteries, flywheels, and so on) can be used to smooth out the intermittent nature of wind power.  When wind power is greater than load in the microgrid, the electricity can be delivered to the national grid.  With storage components installed, electricity could be delivered in a smoother and more predictable pattern.  Not only would this cause less strain on the physical grid, but the stored power could also be used for peak shifting and load-leveling applications, if the storage capacity is large enough.

Along with the entire Asia Pacific region, China currently has a relatively small share of microgrid installations, only about 118 megawatts (MW), according to Pike Research’s Microgrid Deployment Tracker 4Q 2012.  Microgrid deployments are accelerating in Asia, though, and significant increases in wind power should reinforce that trend.

Microgrid Capacity by Region, World Markets: 4Q 2012



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