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On Energy Storage is Critical Issue at Utility Industry's Conference in New Orleans

You are conflating multiple concepts into one conversation Bob, it's difficult to address your questions when you are jumping around so much.  We were just discussing ramping, now we are back to peak load - one is about binary on/off while the other is about the delta and dynamic change.

I would be happy to help you find some resources so we could have a productive conversation. Your last comment is still binary thinking and doesn't reflect dynamic change. Time shifting solar and arbitrage is not a primary driver for storage, it's not about 24/7 solar power.  

June 13, 2015    View Comment    

On Energy Storage is Critical Issue at Utility Industry's Conference in New Orleans

Once again Bob, I hate to do this, but you are not using any data and just guessing at numbers.  Storage systems come in all shapes and sizes - from a handful of kilowatts to hundreds of megawatts.

To replace a peaker, you are not competing with its nameplate capacity - mostly because they are primarily only used about 10-15% capacity factor - you are replacing the application it was performing. By those metrics you could offset the need for a 300 MW facility with a 30-40MW of storage, and avoid the brownfield site, inefficient operation, and wasted investment that goes along with it.

I hope you have found this conversation informative and that you will take the time to learn more about storage systems and their applications. While storage is not the silver bullet it is some times held up as in the media that will solve all our problems, it is a flexible resource that can do many things very quickly and efficiently - and it's value is dynamic, and evolves with the grid.

It's more of a Swiss Army knife, and when you know what all the doodads on your handy tool can do, you will find it very useful for handling many, but not all, jobs.

June 13, 2015    View Comment    

On Energy Storage is Critical Issue at Utility Industry's Conference in New Orleans

Bob, ramping is an important issue and is already having negative impacts on the grid in places like HI, CA, and others.  When large amounts of solar drop off each day, inconveniently at the same time as the system peak, we need a lot of generation very quickly.  Storage and demand response are critical solutions to this challenge, and with more renewables on the way, it is just going to become a bigger hurdle. Do am image search for the 'duck curve' in California , which while just one example, it is indicative of what many grid operators see on the horizon for their systems. 

June 13, 2015    View Comment    

On Energy Storage is Critical Issue at Utility Industry's Conference in New Orleans

Hi Bob- using a system that can accurately follow a grid signal with the exact amount of energy you need in an instant is more efficient.  See PJM's reduction in frequency response as just one example, as I noted above. With a few dozen systems installed on their grid, there are already major reductions and more on the way. 

June 13, 2015    View Comment    

On Energy Storage is Critical Issue at Utility Industry's Conference in New Orleans

Hi Bob - I think that might be an oversimplification of the benefits of a fast-responding, accurate asset on the grid. The underlying principle of why storage is beneficial is that it enables broader system optimization, not the round trip efficiency of any one charge.

Modulating large, slower-responding generating assets (like a natural gas plant) to perform ancillary services is inherently quite inefficient. These either need to be on and idling (burning fuel but not delivering electricity, or even running efficiently), or modulated at the turbine and jumping between different levels of efficiency. Also, taking minutes to respond to a grid signal means that the plant can be following a signal in the wrong direction, wasting energy and needing further correction.

By using storage systems, we can address two big inefficiencies in the system that will help reduce wasted energy. With storage allowing grid operators to more efficiently use thermal plants and deploy the ESS for grid services, we can have those fossil plants at peak efficiency more of the time. And, by avoiding building new combined cycle peaking plants and instead using storage to address those handful of hours each year, we can leverage clean energy or optimized fossil energy to address those rarer seasonal needs.

It does, as you noted, save utilities and consumers money, and part of that savings can be seen in reduced demand for frequency response on the PJM Interconnection following the introduction of pay-for-performance, as one example. Less energy bought for FR service because of the speed and accuracy of storage means less fossil fuel burned, and the energy that is burned is done so more efficiently.

Storage is a multifaceted asset on the grid, and the value exceeds any one application - and while it does lose power in its round trip, it enables us to use energy more efficiently, helps level out variable renewables and maximize their output, and defers unnecessary investments in new transmission equipment and power plants. 

The grid is a large interconnected system and it is aging quickly and not very nimble, and looking at any one node or one energy transaction does not show it's wider impact and benefits. Storage is among the solutions (including efficiency, DR and renewables) we need to deploy to to enable the next generation, efficient electric grid.

June 13, 2015    View Comment    

On Creating an Integrated Grid: Regulators, Legislators Can Help

Great article, and you are correct - the increased deployment of distributed energy assets throughout the grid is shifting the paradigm of how the grid has been run historically.  

To one of the points you have made, I have a thought/question for you. 

I know the APPA has presented information about the degredation and shortened lifespan of generation assets when they are utilized to perform ancillary services (a key place distributed systems can reduce the burden on our infrastructure).  I think this is a key point to keep in perspective in this discussion.  While nat gas generation facilities (small or large) can perform these services, we need to be sure to factor in the overall cost - increased emissions from inefficient dynamic generation, shortened lifespan for these multi-million dollar power plants, and increased downtime and repair for the asset.

Ideally, we would want any generating facility doing what it does best, producing energy and delivering it to the grid.  If we can leverage demand response, smart grid flexibility, and distributed assets like storage and renewables to maintain power quality and resiliency and let a fossil fuel plant run as close to 100% efficiency at all times as is possible, it seems we can make the best use of all the tools that we have at our disposal.  

Ramping generation facilities has a hidden cost that is not typically factored in to our long term and integrated resource planning.  The idea of using smaller generating facilities is plausible, but is indicative of the real need - flexibility and dynamic resources that are responsive, in an instant. 

While market structures like pay for performance are helping to quantify the real value of instantaneous, flexible resources, it would seem a more widespread adoption of policies and regulation that are able to reward systems for the more complex values they provide - resiliency, T&D upgrade deferal, accuracy - is needed to move us forward.

September 28, 2014    View Comment