November 2015 - Power Air Quality Insights 233

Coal-fired power plants emit a variety of pollutants. Some are more harmful than others. The best way to minimize the harm from coal-fired power plant emissions is to assign a monetary value to each ton of each pollutant and then develop a program to minimize the total.

Hundreds of thousands of people are dying each year as a result of fine particles in the ambient air. Some of this particulate is fine flyash emitted from power plants. Much of this particulate is sulfates and nitrates formed by reaction of SO₂ and NO_x with ammonia and other chemicals in the air. This is partially attributable to the SO₂ and NO_x emissions from power plants.

China has recognized the problem and has spent more than any other nation to reduce power plant emissions. Even so there is more that can be done. Other nations such as India are building new coal-fired power plants without the efficient controls now being applied in China. Options for countries are:

The economics are different depending on the location and economy. Turkey needs electricity to bring up its standard of living. It has its own coal supply. It plans to add 80 more coal-fired power plants and eliminate the expensive and uncertain gas supply from Russia. Some environmental groups argue that a better choice would be investment in solar and wind. The less proven economics of this option are offset by the global warming benefits according to the environmental groups. A more certain route is “clean and economic coal.” In general, all the pollutants except a portion of the CO₂ can be eliminated economically.

Pollutants vary in their harm impact. The US EPA has assigned a dollar value for each ton of each type of pollutant which is emitted. Each pound of mercury has been priced at up to $60 million/ ton, whereas CO₂ has been priced at $50/ton. Due to the health problems associated with fine particulate its price tag is $50,000/ton. EPA generates these harm factors in justifying the cost of control technology.

The price tag for each pollutant is certainly debatable. Many would assign higher values to CO₂. Since the impact is longer term, an analogy can be made to inheritance. A wealthy person who has money to leave to his grandchildren will place a higher value on a legacy than will a Syrian refugee who rightly wonders whether he will have grandchildren.

Pollutants such as fine particulate should be considered at least as harmful in developing countries as in the developed because there is no way to avoid their impact. The following table is a harm index based in part on EPA costs.

Pollutant	Harm $/ton
Mercury	60,000,000
Chromium Compounds	5,000,000
PM_2.5	50,000
SO₂	10,000
NO_x	10,000
CO₂	50

Coal-fired power plants generate 250 tons/yr of particulate per MW. Efficiency of capture ranges from less than 98 percent to more than 99.5 percent. So emissions to the atmosphere range from 5 tons per year/MW to 1.25 tons per year/MW or less.

There are presently 2.1 million MW of coal-fired power generation. The difference between efficient particulate control and inefficient control is more than 3 tons/MW or 6 million tons per year. At $50,000/ton, the harm differential is valued at $300 billion/yr. The annual depreciated cost to install and operate the more efficient controls is less than $15 billion/yr.

One approach to reducing particulate also reduces CO₂. A small amount of sorbent is injected ahead of the air pre heater. This reduces the acid dew point and allows extension of the air pre heater, the extracted heat (350^oF to 250^oF) decreases CO₂/MW by 1 or 2 percent. The colder temperature entering the precipitator can result in a 50 percent reduction in emissions. The capital costs are small and the small amount of sorbent needed is not a significant operating cost. So the value in reduced harm outweighs the cost by an order of magnitude.

Mercury reduction can be accomplished very economically where scrubbers are in place. The Chinese have scrubbers on most of their power plants. If they added bromine with the coal and re-emission prevention chemicals in the scrubbers, they could eliminate 20 tons of mercury per year. The value would be $1.2 billion/yr. The cost would be less than $75 million/yr. W.L Gore has a mercury module which can be installed downstream of both wet and dry scrubbers. It can achieve high removal efficiencies at modest cost.

SO₂ scrubbers are required in most countries but not all. Efficiency requirements are typically 90 percent but often 98 percent. Lime wet scrubbers would achieve 99 percent removal. Sodium scrubbers using a double alkali process would also achieve 99 percent removal. Recent dry scrubber developments make this option capable of 95 percent efficiency using lime.

The SO₂ generated in coal-fired boilers is over 100 million tons per year. At least 40 million tons escapes through the stacks. So the potential harm saving is $80 billion/yr. The depreciated costs would be less than $15 billion/yr.

The benefits from NO_x reduction are similar. Selective catalytic reduction (SCR) systems can also assist in mercury removal. The new catalytic filters promise particulate, SO₂ and NO_x removal all in one device.

The potential for revenue generation from byproducts is substantial. Flyash and gypsum are already major revenue generators. Extraction of rare earths from coal flyash with an in situ process may be the best option for this byproduct. Ultrapure gypsum to compete with precipitated calcium carbonate for paper coatings is another option. Hydrochloric and sulfuric acid are already being produced by some plants. Continuing development of byproducts is very likely to increase the value of reduced harm vs. the cost.

The world faces difficult pollution control decisions. For every dollar spent on pollution control, there is an alternative investment in health improvement. For every dollar spent on reducing one pollutant, there is an alternative to reduce another. The most prudent course to make the best investment should include:

The history of climate change research can be measured in decades. Research on particulate pollution is measured in millennia. In England in the middle ages, the color of chimney smoke was used as a basis for regulation. Despite the struggles to eliminate particulate pollution, it remains the pollutant with the most negative impact on human health.

The science of particulate capture has progressed tremendously over the centuries. Today it is known that small particles are more deleterious than large ones. Many regulations are precisely written around particles smaller than 2.5 micrometers in diameter (PM_2.5). Immense numbers of research papers provide great statistical detail based on this size classification.

However, there is a problem. Few particles are spheres. There is also a weight differential. A tubular shaped particle of silica has to be equated to a sphere of lead. The analytical methods use “intelligent classification.” But one should view any conclusions based on particle size with “intelligent uncertainty.”

There are two different worlds of particulate removal. One deals with pollution control of stack gases. The other deals with purifying air for semiconductor cleanrooms. A tester using a high efficiency (HEPA) filter inserted in the stack and remaining clean will pronounce the air as clean as the most pure ambient air on earth.

However, there is another problem. The most pure air on the most pristine mountain is very dirty according to operators of semiconductor plants. In fact this air contains more than 100,000 small particles per cubic foot. As a result, semiconductor plants invest heavily to create Class 1 cleanrooms with less than one particle per cubic foot. They use a technique called condensation nuclei particle counters to make the efficiency measurement.

The complexity and uncertainty relative to the most researched pollutant should inspire us to apply intelligent uncertainty to any and all recommended initiatives. Intelligent classification entails effort. Furthermore, intelligent use of niche expertise is essential. If you need filters for your cleanroom, you do not utilize an expert in stack gas control.

Global warming decisions are enhanced by experts in tens of thousands of niches. The complexities are infinitely greater than those affecting particulate emissions. The scope of advice extracted from each expert should be narrowed to his area of expertise. The expert on sea level rise should not be asked what percentage of electricity should come from solar energy.

Tribal Values: Regulations on NO_x have resulted in extensive investment in selective catalytic reduction (SCR) by power plants. NO_x travels thousands of miles. So the reduction at one source does not necessarily benefit nearby citizens. However, these SCR systems also generate sulfuric acid in varying amounts. The acid is deposited near the stack. In one case in Ohio, the SCR installation resulted in so much acidic damage that the power plant bought and demolished an entire small town (better catalysts have now eliminated this problem).

We have a moral issue regarding tribal values. The world tribe benefits from NO_x control but the Cheshire, Oho tribe lost everything. Global warming will benefit some people and negatively impact others. Each country will have to decide whether to put aside tribal values for the good of the world. Since countries such as the U.S. spend 99.9 percent of resources on the U.S. tribe and almost nothing on the Sudanese or Syrians, the tribal value is a factor which must be addressed.

Net Present Value: Some pollution control benefits are immediate. Others are longer term. What is the comparative value for something which benefits us or benefits our grandchildren? There is no simple or universal answer. Economists use net present value. The annual anticipated interest rate discounts the future value. However, this rate will vary greatly between developing and developed countries. Those who have everything are more interested in creating a better environment for their grandchildren. Those without anything are worried about keeping their children alive for the next month.

Last week China approved a $20 billion pipeline to transfer gas derived from coal to cities thousands of miles away from the north central coal regions where the coal will be gasified. This clean gas will be used in boilers and gas turbines to replace solid fuels which are causing much of the smog in Chinese cities. The immediate benefit will be enormous. Hundreds of thousands of lives may be saved as a result of this program.

The greenhouse gas impacts will also be significant. Some CO₂ will be generated as a result of the gasification process. When the gas is burned in the turbines and boilers, additional CO₂ will be generated. However, if the alternative is imported LNG, then the impact is much less. Some of this gas will replace cow dung, wood chips and coal used in small boilers and cooking fires. In these applications, the gas substitution is a big environmental improvement. Alternatively, China could accelerate its wind and solar program. However, this program could not be accelerated to have the immediate impact of the gasification pipeline.

So this decision by China involves important tribal and net present value considerations. The gasification program will clearly benefit the Chinese but will contribute to the world’s global warming. The gasification program will save many lives in the short term, but may create a less desirable world 50 years from now. It is likely that China cannot be dissuaded from this program at the 2015 United Nations Conference on Climate Change in Paris because tribal values are strong and, as a developing country, China places higher value on the present than do the wealthiest countries.

The solutions to the world’s pollution problems should be considered with intelligent uncertainty utilizing the best combination of niche experts who will provide the most valuable classifications including the tribal and net present values.

McIlvaine Company takes into account the potential impact of these factors in its forecasting and believes that this consideration is necessary for the greatest possible benefit to clients. Information on consulting services can be obtained from Bob McIlvaine at rmcilvaine@mcilvainecompany.com.

Worldwide installations of new gas turbines will average 74,000 MW per year over the next five years. The system sales revenue will be $75 billion per year. GE, Siemens and the other turbine vendors will generate revenues of $20 billion/yr. just for the turbine equipment. This is the latest projection in 59EI Gas Turbine and Combined Cycle Supplier Program published by the McIlvaine Company.

The worldwide installed gas turbine capacity is 1.5 million MW. Purchases of repair parts consumables and upgrades at existing power plants will average $30 billion/yr. Part of this investment will be a result of greenhouse gas initiatives. The least expensive way to reduce the carbon footprint is to make the existing gas turbine more efficient. Adding the steam cycle makes the biggest difference but there are other options as well. Inlet filter replacement for existing units will be more than $500 million. Another $460 million will be spent for SCR systems and catalyst per year. The market for replacement parts for pumps and valves will be significant.

The gas turbine equipment suppliers purchase most of the components they furnish as part of turbine packages. Complete turnkey systems, including the gas turbine, steam turbine, cooling towers, HRSG, SCR, etc. are sold by a number of companies who do not manufacture turbines. Despite the fact that the purchaser could be an end user, a system supplier or an EPC, the number of companies purchasing filters, treatment chemicals, instrumentation, pumps and valves is very limited.

Those suppliers selling hardware for new power plants need to contact the operators, the system suppliers and the engineering companies. Those selling consumables have a more limited target.

It terms of end users, there are less than 100 power plant operators who will buy most of the equipment and consumables. E.ON has 23,000 MW of gas turbines in operation while Calpine has 26,000 MW. Together they have over 3 percent of the world’s installed capacity. The number of system suppliers and engineering companies is also limited. Black & Veatch, Burns & McDonnell, Sargent & Lundy, Bechtel, Kiewit and a few other U.S. based architect engineers do a lion’s share of the engineering work.

The number of equipment vendors is even more limited. GE had a 49 percent of the global gas turbine market last year, followed by Siemens with 23 percent, Mitsubishi Hitachi with 17 percent and Alstom with 2 percent. With the purchase of Alstom, the GE share will rise above 50 percent. In addition, GE has made a huge investment in a new more efficient design which may boost their share well above 50 percent.

GE’s new flagship, HA Turbines, will be the largest and most efficient in their class. The first delivery was to EDF’s Bouchain combined cycle power plant in France in August and is now being installed. The first U.S. order is from Exelon. Four 7HA turbines intended for expansions at the Wolf Hollow and Colorado Bend plants in Texas are expected to come online in 2017.

The 50-hertz 9HA and 60-hertz 7HA both come in two different models. The 9HA.01 is rated at 397 MW in simple cycle mode and 592 MW in 1 x 1 combined cycle mode, while the 9HA.02 is rated at 510 MW in simple cycle and 755 MW in combined cycle. The 7HA.01 and 7HA.02, meanwhile, are rated at 275 MW and 405 MW and 337 MW and 468 MW, respectively.

Both designs can achieve better than 41 percent efficiency in simple cycle and more than 61 percent in combined cycle. GE says the 9HA.01—the model slated for Bouchain—can reach full power in 30 minutes and ramp at 60 MW per minute.

GE already has $1 billion in firm orders for 7HA and 9HA turbines—16 units so far—and 53 potential projects around the world have opted for the turbines. GE hopes to sell up to 500 of the new design by 2030, which could represent up to half of its gas turbine sales.

For hardware purchased directly by gas turbine suppliers, one company represents more than 50 percent of the potential and three companies combine for 90 percent.

Most suppliers have a direct sales force for large customers and a network of sales representatives or distributors for the balance of sales. Since 70 percent of the sales will be to less than 100 large operators, equipment suppliers and engineering companies, it is important to focus on the direct sales effort. McIlvaine has developed Detailed Forecasts of Markets, Prospects and Projects which is included along with 59EI Gas Turbine and Combined Cycle Supplier Program.

Projects have recently been proposed for both the east and west coast of the United States. A location not far from Hearst Castle near Morro Bay has been named as a site for California’s first offshore wind farm. Trident Winds has filed early paperwork with Morro Bay city officials for a plan to install 100 floating turbines each up to 636 feet tall about 15 miles off the San Luis Obispo County shoreline. The project would generate 1000 MW of electricity.

DONG Energy, the world’s largest developer of offshore wind farms, is proposing a 1000 MW wind farm 15 miles south of Martha’s Vineyard. The company recently acquired one of the leases for a stretch of ocean the U.S. government has designated for wind farms. Seeking to distinguish the project from the troubled Cape Wind project the company said this project will be much further out to sea and should therefore receive less opposition from oceanfront property owners.

Wind projects both on and offshore are tracking in McIlvaine’s Renewable Energy Projects and Update.

McIlvaine webinars offer the opportunity to view the latest presentations and join discussions while sitting at your desk. Hot Topic Hours cater to the end users as well as suppliers while the Market Updates cater to the suppliers and investors. Since McIlvaine records and provides streaming media access to these webinars there is a treasure trove of value only a click away. McIlvaine webinars are free to certain McIlvaine service subscribers. There is a charge for others. Hot Topic Hours are free to owner/operators. Sponsored webinars provide insights to particular products and services. They are free. Recordings can be immediately viewed from the list provided below.

DATE

UPCOMING HOT TOPIC HOUR

UPCOMING MARKET UPDATES

November 12, 2015

Dry Scrubbing
Expansion of the dry scrubber decision guide for power plants,
incinerators, and other applications involving SDA, CFB and
DSI.
Click here to register

December 3, 2015

NO_x Reduction
Decision guide to selection of SCR and SCR systems,
ammonia injection, reagents, catalysts for power plants
refineries, incinerators, chemical plants and other applications.
Click here to register