The New Hampshire Energy Picture – Part 3: What Happens to the Energy that is Supplied to the State?

In my last post we looked at the direct use of energy in the State. We followed the various components of the energy supply into transportation, residential and commercial heating, industrial use and the generation of electricity. However, I also made the point that electricity is not an energy source - it is an energy transfer medium. It is the way we get the energy out of a lump of coal or a nuclear fuel rod so that it can power the coffee maker in our kitchens. I think we can all agree that buckets of coal or enriched uranium in the kitchen do not work well in powering the toaster and microwave. Therefore, if we are to determine the final allocation of energy use in NH, we have to follow the flow of electricity into its final end use: that is the focus of this blog post.
 

Here is the NH Energy picture I have been working through in the last few posts. In the last post we looked at energy flows from the left column to the center one. This week we are going to focus on the energy flow from the center column to the rightmost one.

So let's start off by looking at the largest slice of the center column so we can determine what happens to all the energy that goes into the production of electricity. We note that 224 Trillion BTUs, or 55% of our total energy supply, goes into the production of electricity. The arrows radiating out from the electricity slice tell the following story:

Approximately two thirds of the energy that goes into the production of electricity is lost as waste heat during the energy production and transmission process. If you are not familiar with electricity production, this might be a rather startling fact. It indicates how inefficient transmission and especially the generation of electricity is when only 35% of the energy input ends up as useable electricity in our homes and businesses. This is a result of the physics of the electricity generation process, and since the advent of commercial scale electricity production, engineers and scientists have been working hard to improve conversion efficiencies. The first commercial electricity generating operation was established by Thomas Edison in New York in 1882. Edison's first operation converted less than 2.5% of the energy in coal to electricity. The average coal plant operating today has a conversion efficiency of ~28% and the latest generations of combined cycle coal power plants have conversion efficiencies of the order of 45 to 50%. We have indeed come a long way efficiency-wise, but we cannot escape the fact that electricity generation produces a lot of waste heat. Not only is energy lost in the generation process, but some of it dissipates during transmission where losses are typically of the order of a further 7%.

The other distribution arrows in this figure show us that 7% of the energy that into goes into electricity production ends up as electricity routed to our homes. A similar amount ends up in commercial operations and industrial usage accounts for 3%. Finally, and for me quite interestingly, a significant 17% ends up as electricity that is exported out of state.

To get a better view as to what happens to electricity after its production, I have sliced and diced the data a little differently in the figure below. I have subdivided the tall electricity slice into its two main components – electricity and waste – because I wanted to examine the allocation of generated electricity in the state. The subdivided column shows that the electricity generation slice is one third generated electricity and two thirds waste heat. Now, if you follow the arrows radiating out on the electricity only piece, you can see that, of the electricity generated in the state, 21% is used in our homes, 21% in our commercial operations, 9% is used to drive our factories and an impressive 51% is exported out of state into the New England Electricity Pool.

It is this exported pool of electricity that often gets politicians, ordinary folks and even less ordinary folks worked up into an absolute lather here in New Hampshire. It has been used at various times to justify the closing down of the Seabrook Nuclear power plant, our coal burning plants and even the Northern Pass project. In a future post I will weigh in on this debate but for the moment you should know that my viewpoint is a highly pragmatic one. I believe that as we continue our rather slow transition to renewable energy, we need to draw upon as many different energy sources as we can so that we are not trapped and reliant on one or two energy sources sometime in the future. Diversification in energy supply, just like picking investments, reduces future risk and my focus is on reducing risk and creating a sustainable future for my children.

It is crucial to note that even though we presently export 50% of the electricity produced in the State, this has not always been the case, and it might not be the case in the future. Prior to the Seabrook Nuclear plant, we were net importers of electricity. We are part of a regional and national pool and at this time we are in the good position to be making a positive contribution.

This final figure combines the allocation of the energy that goes into electricity production with the other energy flows we saw in my previous post. From this figure we learn the following:

• In our homes 71% of our energy comes from fuels, largely fossil fuels, for direct heating applications. The remainder of the energy supplied to our homes is from electricity usage.
• For our commercial businesses 58% comes from direct heating and 42% from electricity. The higher percentage of electricity use in our commercial operation is likely due to increased use in lighting for displays and air conditioning in the summer.
• Our factories are more like our homes where 75% of energy use is from direct heating and 25% is from electricity.

Finally, if we examine the percentages in the leftmost column and working from the bottom up we learn that, of the 409 trillion BTU of energy supplied to the state, 36% of it is lost as waste heat during the generation and transmission of electricity, 9% leaves the state as exported electricity, 7% is used to power our factories, and 9% is used to keep our office buildings and stores lit up, warm and air conditioned. Our homes are responsible for 13% of NH's energy appetite and transportation uses up the remaining 26% of our energy supply.

So there you have it. After slogging through three detailed posts you should now have an understanding of NH's energy picture and a good idea of where our energy comes from, how it is used, where it ends up and how much is wasted as a result of electricity generation.

Before I ride off into the power line sunset shown on the background of my blog, some of you might be ready to point out that this picture is not quite complete: if I have shown how much energy is lost as waste heat during electricity generation, I should have done same for the energy used in transportation and that lost from our homes and businesses. I totally agree with you, but that brings in another level of analysis, more complications, more columns and spider webs of arrows and, I think, for the moment, we have all had enough of those. There is a better way to show this and that brings me to the topic of flow diagrams which I will be discussing in my next post.

Let me know if this rather lengthy explanation over the past few posts has helped you understand the statewide energy flows and, as always, I am interested in your opinion.

Until next time, remember to turn off those lights when you leave the room.

Mike Mooiman

Franklin Pierce University

mooimanm@franklinpierce.edu

1/13/2012

 

 

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