Category Archives: Electric Grid

Our Electric Grid – Renewable Energy Sources, Part 3

Welcome back! This week I am beginning to focus on some of my concerns about renewable energy, which will continue into next week, and will move into discussing some of the negatives that aren’t being publicized – Again, I am not against renewable energy, but I’m afraid that we are pushing for something, which we really don’t understand the consequences. Personally, I believe we should continue to focus on renewable energy, while studying it – I believe our best bet is for us to have a balanced power portfolio among the different power sources.

In my first post in this series, I asked if anyone new which type of generation source caused the largest immediate death toll – I bet a lot of people immediately think of nuclear, but that would be incorrect. The largest catastrophe in power generation history goes to hydro-electric. In August of 1975, the Banqiao Dam in China failed after a record flood, resulting in 26,000 people dying immediately, and an estimated 145,000 people died from epidemics caused by water contamination.   http://www.britannica.com/event/Typhoon-Nina-Banqiao-dam-failure

In contrast, only one nuclear accident has been attributed to more than ten deaths. That would be the Chernobyl disaster in Russia on April 26, 1986. I’m sure people have heard all kinds of numbers about the Chernobyl disaster, however, there were 31 deaths that occurred within a short time after the disaster, 2 immediately died from explosions, one from a heart attack, and 28 first responders died from Acute Radiation Sickness (or syndrome).

The World Nuclear Organization has claimed that the death toll will roughly be between 4,000 and 9,200 (between emergency and recovery workers, and residents in the contaminated territories). Now I will also say that there are also people saying that the official reports are drastically underestimated, and claim that as many as a million people have died from Chernobyl (http://www.globalresearch.ca/new-book-concludes-chernobyl-death-toll-985-000-mostly-from-cancer/20908) – I don’t know, but the official report is less than 10,000 total.

http://www.world-nuclear.org/info/Safety-and-Security/Safety-of-Plants/Appendices/Chernobyl-Accident—Appendix-2–Health-Impacts/

http://www.world-nuclear.org/info/Safety-and-Security/Safety-of-Plants/Chernobyl-Accident/

http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/chernobyl-bg.html

https://en.wikipedia.org/wiki/Nuclear_and_radiation_accidents_and_incidents

I believe Chernobyl was a terrible disaster, and is worse in some aspects than the Banqiao Dam due to victims facing mutations, mutations in their children, cancer, and among other issues. My goal with this information is to inform people that we underestimate a lot of risk, and take many things for granted without thinking about it or researching it – just following the news…

Please join me next week for more!

Our Electric Grid – Renewable Energy Sources, Part 2

Alright, back to my original question I always get asked – Why can’t we just go to all renewable sources of power immediately?  My previous blog post on Renewable Energy

Before I get started, I want to be clear – I am not against renewable energy. I just wish to explain why it isn’t easily feasible to quickly convert, and impossible to completely convert to 100% renewable sources. I would also like to express some of my concerns (in a future article) about renewable energy that I have not seen addressed yet.

The primary problem is that the most sought after renewable sources (wind and solar) do not provide a stable power generation throughout the day – their output varies with their power source. As the sun fades from clouds or other causes, the power generated from solar panels fade away with it, and as the wind dies down, wind turbines power generation die down with it. Also, our power demand fluctuates throughout the day as well:

Summer Load and Wind Availability

http://www.continentalecon.com/publications/cebp/Lesser_PTC_Report_Final_October-2012.pdf

The black dotted line is the average electrical demand, the solid black line is the summer electrical demand, and the red doted and dashed lines is the electrical generation available through wind. If you notice, it is exactly opposite – the wind turbines are at their minimum generation abilities around the peak energy demand times.

Grid-Graphic-Cali-Wind-Solar-Generation

Now, on a normal day, solar power follows the demand relatively closely, but it actually begins dropping off at the very peak of the power demand.

These graphs are smoothed out, and are over a large scale. In a localized area the demand is much more chaotic – fluctuating by the second.

Even though solar and wind look like they can balance each other, their variations can wreak havoc on the electric grid – every time you flip on a light switch, you change the demand on the system and something somewhere has to be available to increase the power generation instantaneously. Essentially, this means that a coal or nuclear plant has to be backed down from generating 100% of its capabilities, to be able to provide for those fluctuations.

What does that mean? Significantly higher costs. When you ask anyone how much it costs for solar power, all you will hear in return, is the purchase price of the panels, the necessary equipment, and the cost of installation. However, this added volatility to the grid causes larger plants to reduce their generation, but having to keep that power generation readily available to create a buffer for the variations caused by the solar panels. Although this is not a direct cost to you, it is a cost that our society has to account for (also discussed for wind here: http://www.continentalecon.com/publications/cebp/Lesser_PTC_Report_Final_October-2012.pdf).

A lot of the information we have today has changed drastically over the years – especially for renewable energy. Before the last ten years or so, there just weren’t nearly as many facilities. Therefore, we didn’t have the large dataset of information that we have today.

Please join me again next week on this topic – I will introduce some of my personal concerns about solar and wind power that I haven’t seen discussed yet. Please follow me and leave comments!

Our Electric Grid – Renewable Energy Sources, Part 1

Being in the power industry, and especially since I am currently working at a coal power plant, I get a lot of people asking me about Renewable Energy. More specifically, why can’t we just go to all renewable energy, what’s the hold up? So I’d like to spend the next few blogs in my Our Electrical Grid series to discuss some of the ins and outs of renewable energy.

In 2014, in the US, renewable energy accounted for less than 15% of our total power generation. There are 5 main types of renewable energy sources right now:

  1. Hydroelectric – 6%
  2. Wind – 4.4%
  3. Biomass – 1.75
  4. Solar – 0.4%
  5. Geothermal – 0.4%

http://www.eia.gov/tools/faqs/faq.cfm?id=427&t=3

about-renewable-energy

http://www.occupy.com/article/renewable-energy%E2%80%94-jobs-producer%E2%80%94wins-vote-north-carolina

Both Biomass and Geothermal utilize the basic steam cycle. A Biomass plant is much like a coal plant, except it has special processes to handle and combust the biomass material. While geothermal extracts its heat from below the Earth’s surface, which is primarily from the decay of radioactive elements. Please review my Electrical Generation Basics post for this topic to review the steam cycle.

Hydroelectric and wind are both similar, as they directly convert their energy source into a rotational motion – The sole purpose of the steam cycle is to cause the turbine to rotate. After the energy is converted into a rotational force, hydroelectric, wind, biomass, and geothermal all use a similar type of generator to convert the rotational energy into electrical energy. You may also review my Electrical Generation Basics post for this topic to review the basics of the electrical generator.

Solar is very different from the other renewable energy sources. It essentially uses a photosynthesis process to convert the sun’s energy into electricity. I will cover this topic in a later post on my renewable energy series.

For my next blog post in this series, it is important to understand the sources of energy for renewables – Biomass, Geothermal, and Hydroelectric are the only renewable sources that provide a consistent source of electricity 24/7. Next week I will be discussing some of the negatives of renewables – Please sign up and follow me, or check back next week for more!

Does anyone know what type of electrical generation source caused the largest immediate death toll? Please leave an answer in my comments section, and I will provide you with some more insight next week!

Our Electric Grid – Fuel Sources Part 2 (Nuclear Fuel)

In Our Electric Grid – Electrical Generation Basics, I introduced the basic steam cycle in my discussion. In Our Electric Grid – Fuel Sources Part 1, I presented the basics about coal and gas fuel sources. In this part, I am introducing the basics of nuclear fuel sources.

Now I will mention that there are numerous types of reactor designs, including different nuclear fuels, different fuel mixtures, boiling water reactors, pressurized water reactors, and different methods for controlling nuclear reactors. In my future blogs, I will be discussing the GE Hitachi Nuclear Energy – Economic Simplified Boiling Water Reactor (ESBWR), which is one of the reactors I studied for my bachelor’s degree. If you would like me to discuss another type in the future, please let me know in the comments below.

ESBWR

In the ESBWR reactors, uranium 235 (abbreviated U-235). U-235 is actually found naturally, and is mined. Although, natural uranium only contains about 0.7% U-235, the remaining 99.3% is primarily a U-238 isotope, which isn’t useful for reactor fuel. Numerous facilities exist that enrich the uranium by physically separating the isotopes of uranium. Civilian plants typically use 3% – 5% enriched uranium (they are prevented from using anything higher due to nuclear treaties), which is a level that is low enough that it is impossible to create a nuclear weapon with. Theoretically, one kilogram of U-235 can release as much energy as 1500 tons of coal, if it were able to fission 100% of the U-235.

Almost looks like lead or a sort of metal

U-235 – Almost looks like lead or a sort of metal

At the highest level, you can think of the uranium simply as a hot rock. Inside the reactor, while it is operating, the U-235 fuel is fissioning. (In a later blog posts, I will discuss how the process of how fission works in these reactors, safety concerns, and how they are controlled.) The process of the U-235 fissioning produces tremendous amounts of energy in the form of heat. Water is in contact with the fuel rods inside the reactor, which allows for the heat to transfer from the fuel into the water. In the ESWBR plants, the water is actually allowed to boil inside the fuel channel, which creates the steam. From there, it starts the basic steam cycle, as I mentioned in my Our Electric Grid – Electrical Generation Basics post.

nuclearreactor

I will continue discussing nuclear power in the near future, but next week I will begin introducing some information about renewable energy sources – so stay tuned and leave comments/suggestions!!!

Our Electric Grid – Fuel Sources Part 1

Last blog post I discussed some of the basics about how electricity was generated, and introduced the basic steam cycle. This blog I would like to share some information about the primary heat sources for steam cycles of power plants; coal, natural gas, and nuclear.

Coal Plant1

In order to increase the efficiency of coal, which also helps minimize emissions, coal is ground up into a very fine particulate. This is performed inside of a Pulverizer, which uses large steel balls to crush and grind the coal into the very fine powder. The pulverizer is also combined with a Primary Air fan, which blows a large amount of air into the pulverizer that serves two purposes:

  • Blows the pulverized coal out of the pulverizer
  • Mixes a specific amount of air with the coal fines to increase burning efficiency

After the coal leaves the pulverizer, it is directed into coal burners, which assist in directing the coal, and the fire to maximize efficiency and minimize emissions. At the burners, coal is lit off into fire (initially by a natural gas flame, but the coal fire becomes self-sustaining and the natural gas is removed). The fires heat the tubes inside the furnace, which contain water, causing the water to boil into steam. The steam is then “superheated” by sending it through another heat exchanger downstream from the fires. After being superheated, the steam is then sent to the turbine, starting the steam cycle.

Pulverizer

http://www.powermag.com/pulverizers-101-part-ii/

Coal Plant2

There are two different methods for using natural gas – through a gas furnace, or by using a gas turbine. A gas furnace is perhaps the simplest of all the power sources for the steam cycle plants – it is simply done by burning natural gas through burners, similar to how coal is burned after it is pulverized.

The gas turbine is not necessary for a steam cycle, however, they are typically used in conjunction with a steam cycle to increase the efficiency of the gas – these are called combined cycle natural gas plants. In a combined cycle natural gas plant, natural gas feeds a gas turbine, where it is mixed with air and burned. The burning creates additional gasses, and heat, causing the gasses to expand, building up pressure. This pressure from the gas and heat is used to drive the turbine, which also has a generator attached to it. After it exits the turbine, the gas is directed through a water heat exchanger, where it boils the water to steam – this allows these plants to reclaim some of the energy, which would have been lost in the form of heat. Some of these plants also have supplemental natural gas burner elements to aid in controlling and increasing the output of the steam cycle. (http://energy.gov/fe/how-gas-turbine-power-plants-work, https://www.edfenergy.com/energyfuture/generation-gas)

GasTurbinePlant

Thanks for continuing to read my blog! Next week I will continue this discussion of fuel sources, moving to nuclear fuel – please check back, and leave comments!

Our Electric Grid – Electrical Generation Basics

Last blog I shared some basic information about the power grid, which I will expand on later. So for this blog post, I would like to share some basic information about how power is generated, which I will also expand on.

Electricity is created by energy transformation – we are taking one form of energy (chemical, nuclear, kinetic, wind, or electromagnetic radiation) and converting it into the electrical form of energy. The majority of power generation in our country is through the use of a Steam Cycle – Coal, oil, nuclear, natural gas, and others all use steam cycles. Steam systems are actually extremely complex, and very precise, but from the high level view a steam cycle uses a system of components to convert the fuel source into heat, which is intern used to heat up water and convert it into steam. The energy in the steam is then directed through a turbine, which provides kinetic energy to the electrical generator through the attached rotating shaft. The steam is exhausted from the turbine and condensed back to water for reuse. See the image below for a simplified example:

SteamCycle1

Electricity is a unique, interesting energy source. It is closely related to magnetism, and can be generated through the use of magnetism – simply passing a magnetic field by an electrical conductor, such as a piece of copper wire, will induce a voltage in the wire as the magnetic field passes it. The voltage is only induced as the magnetic field is moving, and ‘cutting’ through the wire. On the other side of that principle, when current is passing through a conductor will actually create a magnetic field. Electromagnets are created by coiling copper wire and passing electric current through the wire. These principle are how we generate electricity in our generators. In most generators, the rotating portion is just a big electromagnet, and around the armature is a bunch of coils of wire. Therefore, as the steam rotates the turbine shaft, it rotates the electromagnet causing the magnetic field to ‘cut’ the wires and induces a voltage – electricity!  This is a simpler drawing of a 1 phase generator:

AC Gen1

Power plants actually generate electricity in 3 phases, without getting in too deep yet, just consider it as 3 different power lines from 1 generator:

generatoranimation

In reality, these systems are much, much more complex, but I’m sparing the details for some more advanced blogs later, but I’ll share a little bit for future topics. The generation systems have to maintain a certain voltage output, and frequency, otherwise it would damage our electronic devices. Therefore, there are a lot of additional monitoring systems, protective systems, and regulation systems – the turbine speed is regulated to maintain generation frequency, and the electromagnetic field is also regulated to maintain the voltage output of the generator.

For next week I will be discussing how the different fuel sources get broken down and used to create heat, and I’ll also discuss a microcontroller project I’m currently working on using an Arduino Mega – Follow my blog and stay tuned for more!

Our Electric Grid – The Basics

Power GridI thought I would start out my blogging by sharing some basic information about one of the essential elements to our lives – Our Electric System.

So, really, what is our electric system? At the highest level, our electric system starts with power generation. In the U.S. we have over 7000 power generation facilities, which includes coal, natural gas, nuclear, petroleum, and renewable energy sources (I will cover the basics of how each type of plant generates electricity in the near future). These facilities generate electricity, which they send out through transmission lines to various points. As electricity began developing, facilities began adapting our standard 60 Hz system (which I will explain later), and they started connecting multiple facilities together for improved reliability. Today, our electric system is split up into three different sections, as seen in the image above (image from NPR), with interconnections to the other sections – creating a more reliable source of power for our country.

Since our country has suffered a couple of severe blackouts, and because our power grid is essential for national security and our wellbeing, the U.S. government has created a regulation agency. This agency is called NERC (North American Electric Reliability Corporation). NERC’s responsibility is to ensure the reliability of our electric systems by developing operational, maintenance, and basic engineering standards for “the bulk power system” (basically all generation facilities, and large industrial loads). NERC is split up into a few different regions (please open link to view map). Each region monitors companies that are tied into the bulk power system, and are responsible for auditing companies, finding best practices, and fining companies for compliance issues.

Another organization to assist in the reliability of power systems are RTOs (Regional Transmission Organizations). These RTOs have massive computer system that have a model of the all the aspects of the grid in their area (power generation plants, system transformers, and various large loads). The computer systems monitors all these aspects of their part of the grid in real time, along with forecasting generation and load figures from companies, and determines if there is an excess or shortage of power in the area. In order to balance the load across the grid, and minimize system limitations, the RTO will set power prices for each facility to economically encourage them to balance the load. These power prices can change every 5 minutes, and facilities get paid or charged by the hourly average of those prices. The RTO for my plant is called MISO (Midcontinent Independent System Operator). If you follow this link, you can see the power prices in my region, which will update every 5 minutes. See if you can find my plant – It’s at the bottom of Indiana with the LMP Point: SIGE.WARR4SIGE.

That’s all for this post! I’ll be posting some additional information about the grid, power plants, and moving to other technologies in the near future. Please leave comments!