Generac Grid Services Blog

Guest blogger Peter Asmus of Navigant Research posts this week about the widening use of distributed energy resources around the world, virtual power plants and distributed energy resources management systems.

As distributed energy resources (DERs) continue to proliferate, so do the reliability challenges associated with the world’s aging grid infrastructure. The diversity of resources added to the power grid include plug-in EVs (PEVs) and rooftop solar PV coupled with energy storage devices at residences. As the grid was not designed for two-way power flows, these trends create challenges and opportunities for vendors and grid operators.

Enbala founder Malcolm Metcalfe had the opportunity – and honor – of learning the answer to this question first hand when he met with Queen Elizabeth II earlier this month.  Yep, he chatted with the Queen.  At Windsor Castle. And it turns out that she shares a dream with Malcolm – the dream of a clean energy future where energy poverty no longer exists for the 1 billion people in the world who are living without electricity today and the 3.8 billion more whose energy sources are insufficient, unreliable, dangerous or prohibitively expensive. 

Guest blogger Peter Asmus of Navigant Research posts this week about virtual power plants, distributed energy resources management systems, microgrids — and the way in which Alectra is bringing them all together to meet its customers energy needs and its own grid reliability requirements. 

Electricity is a multidimensional product that requires constant fine-tuning. Otherwise, the lights go out, resulting in substantial lost economic activity. The challenge of accomplishing this task has become increasingly difficult as the fleet of distributed energy resources (DERs) begins to take over electricity resource pools. Beginning in 2018, annual centralized power resources began to give way to distributed generation and a more diverse DER mix. I noted last year that this transition was likely.

The Question

The world is changing. This isn’t news, of course. In fact, it’s rather old news – the world has changed. And the composition of the power grid has changed along with it. More roofs have solar panels. More garages house electric vehicles. The devices consumers plug into outlets have radically different load profiles than the devices of previous generations. Today there is an increased prevalence of wind farms, smart inverters, batteries and many other distributed energy resources (DERs) at the grid edge.

All these DERs offer tremendous potential through control and optimization. But while this capability presents copious opportunities, it also creates a few headaches, particularly for grid operators, often miles away (literally and figuratively) from where the DERs are located.

Yet DERs are becoming so entrenched in the daily operations of the grid that it’s tempting to ponder just where their limitations lay. With advancements in technology and business models, many innovators are looking to increase value from DERs, which leads to the latest question surrounding the capabilities of these assets: Can DERs play in utility and wholesale markets?

For more than 100 years utilities have supplied electrical power to customers and have done so with good reliability. The principle is simple. Loads may do as they wish. They may be random or intermittent and generally are not individually monitored by the utility.  Generation, on the other hand, MUST be both dispatchable and monitorable, and electric system operators must be able to manage the real and reactive power from a generator.

Historically, utilities have become very adept at managing generation capacity to maintain a continuous balance between supply and demand. But today, the world is faced with a need to reduce or even eliminate carbon emissions, which complicates the supply-demand balance. Most electricity in the US, for example, is generated by burning fossil fuel. This needs to change, along with change to the electricity supply system and the direct customer use of fossil fuel.  We are looking to remove the steady performers, and to replace them with supplies that are intermittent and perhaps random, all the time maintaining a balance between supply and demand.

The California Duck Curve reveals a potential costly issue for utilities and their customers. The annual peak load appears to be continuing to grow -- because it occurs after dark when there is no solar power being generated -- yet energy sales may be declining with the growth of distributed solar generation during the day. This results in the need to continue to expand the grid, but without the sales revenue to support the added capital expense, presenting a Catch-22 that utilities are struggling to overcome.

Here’s a little something you can chew on if you are sitting down to eat one of the 46 million turkeys Americans will roast this Thanksgiving. The latent thermal storage in all those turkeys could provide 4.32 gigawatt hours (GWh) of energy. According to the Energy Information Administration, the average U.S. home used 10,766 kWh in 2016. That means all that thermal storage in Thanksgiving’s main-dish favorite could power some 400 homes for an entire year.

So, how do you tap that energy? You can’t exactly roll into your garage and plug a hybrid vehicle into a turkey. But, you can use a turkey’s thermal storage capacity the same way you tap the thermal energy in the cooler that’s chilling the beer you might drink during a holiday football game. The mass of the turkey allows the grid to utilize a cold storage facility as an energy storage system.

I read Milton Caplan's post entitled "An Inconvenient Reality: Nuclear Power is Needed to Achieve Climate Goals." I can certainly support much of the article, but it seems to miss one very key point and that is the need.

Science has told us that we need to reduce carbon emissions. The trouble starts when the political masters translated that to mean that we need to fully get rid of fossil fuels and switch entirely to renewables – and while at it, we need to get rid of nuclear as well. I wonder where that latter part came from? Nuclear is clean. Why was it lumped in with fossil fuel? Much of the opposition was based on past fears. The movie Pandora’s Promise shows how many of the opponents have, after a careful look, reversed their views..

REDEFINING SUCCESS FOR A DISTRIBUTED ENERGY GRID: THE THREE TENETS

When it comes to effectively leveraging distributed energy resources (DERs), there are three critical success factors that any DER management system or Virtual Power Plant (VPP) must embody. In a previous blog we focused on Tenet #1: the importance of speed.  

In today’s blog, we address another of the top three criteria: accuracy. Just as the question “how fast is fast enough” was answered with “it depends,” so too does the question “how accurate is accurate enough” have the same response. The criticality of accuracy depends on what the distributed energy resources are being dispatched to do.  

Our blog post this week was authored by our friends and fellow Coloradans at the Rocky Mountain Institute (RMI). We think it's one of the best posts we've read in a while, and RMI kindly gave us permission to share it. 

In April, U.S. Secretary of Energy Rick Perry announced a 60-day study on electricity market design and grid reliability, meant to assess to what extent current market designs fail to adequately compensate “baseload” (i.e., coal- and nuclear-fired) power plants.

The memo commissioning the study presents as “fact” a curious claim: “baseload power is necessary to a well-functioning electric grid.” This notion has been thoroughly disproven by a diverse community of utilities, system operators, economists, and other experts that moved on from this topic years ago. To these practitioners, this premise seems as backward as if President Eisenhower, instead of launching the interstate highway system, had called for restudy of the virtues of horse-drawn carriages.

Today, the grid needs flexibility from diverse resources, not baseload power plants. Leveraging market forces to help us decide between options offers the best chance of avoiding the multitrillion-dollar mistake—and gigatons of carbon emissions—of blindly reinvesting in the past century’s technologies.