PRB Tech Notes: Give Coal Handling the Priority It Deserves

Over the past 17 years — dating back to the 1990 Clean Air Act Amendments and including the introduction of retail competition — coal-fired power plants have become much cleaner and more efficient. Utilities have spent many billions of dollars to install pollution controls for regulatory reasons, and only slightly less to upgrade turbine-generators and extend equipment life for economic reasons. Similar levels of investment will be needed going forward.

The attention to retrofitting burners, reblading turbines, rewinding generators, fine-tuning boilers to maximize their efficiency and minimize fouling and corrosion, adding precipitator fields and scrubbers and selective catalytic reduction systems, and switching to my favorite generation fuel — Power River Basin coal — is well-deserved. But in an era of tight utility budgets, every dollar spent on these projects represents one not spent on an often-overlooked but equally important area of coal plant operations: the coal yard and coal-handling systems.

In the Zone

I think of the typical power plant as comprising four zones or business units:

  • Zone 1: Coal handling

  • Zone 2: Boilers and combustion systems

  • Zone 3: Turbines, generators, and auxiliaries

  • Zone 4: Postcombustion emissions control

In my experience, the industry has pursued excellence in only three of these operations areas: Zones 2, 3, and 4. Yet efficient and cost-effective coal handling (Zone 1) is as critical to plant profitability as any of the other three zones.

An Automotive Analogy

To understand why coal yards and coal-handling systems deserve more attention, consider the parallels between the major systems of a power plant and the major systems of your car or truck. Your vehicle has a gas tank, gas pump, and gas lines (a fuel-handling system, Zone 1); fuel injectors and an engine block with requisite attached hardware (like a boiler, Zone 2); a drive train to bring the mechanical energy of the crankshaft to the wheels (the turbine-generator, Zone 3); and an exhaust system with a muffler and catalytic converter for reducing noise and air pollution (downstream emissions controls, Zone 4).

Now answer the following questions about your car or truck’s fuel-handling system:

  • Can your engine run without fuel? No.

  • If your fuel pump breaks down, is there another way to supply the engine? No.

  • When you see or smell a fuel leak, do you keep driving? No (you fear a fire or explosion).

  • If the system delivers a contaminated fuel to your injectors, fouling them, does that reduce your mileage? Yes (and it also increases your operating costs — lower fuel economy means more trips to the pump).

Each of these questions also is applicable to your coal yard and coal-handling system. The first two should remind you how important both are to your plant’s availability. The last two reflect today’s new attitudes toward coal-handling safety and housekeeping: Most plants now have zero tolerance for coal spills and accumulated coal dust that could spontaneously catch fire.

Making the Business Case

Need some statistics to justify spending on improvements to your coal yard and coal-handling system? Here are three that should give any business unit manager pause:

  • At the typical plant, coal handling is the responsibility of 18% to 25% of employees.

  • A coal-handling system delivers 100% of the fuel that represents 65% to 75% of most plants’ operating costs.

  • For a plant that burns 5 million tons of coal per year, reducing the loss and waste from a coal yard and coal-handling system by 50% will typically produce annual savings of at least $1 million.

There’s an upside to the neglect of Zone 1 in power plants over the past two decades. Equipment vendors, consultants, and utility end users have seen in the stagnation an opportunity to develop new coal-handling technologies and practices that improve operational efficiency and cut costs. For example, advances in coal pile management and reclaim practices can minimize unit derates, which erode a plant’s bottom-line numbers.

Leading utilities have undertaken initiatives to make their coal yards and coal-handling facilities "best in class." They understand that it is imperative to run Zone 1 (as a business unit) as efficiently as they do Zones 2 through 4. The time is right for you to follow suit and balance investments in all four zones of your power plant. Here’s hoping you’ll do what’s necessary to take your coal yard and coal-handling systems to the next level.

Burn PRB Coal? Learn How to Do It Better by Joining the PRBCUG

This year’s annual meeting of the Powder River Basin Coal Users’ Group will be held in Chicago at ELECTRIC POWER 2007 (www.electricpowerexpo.com) from May 1 – 3. Last year’s meeting in Atlanta drew more than 320 staffers of gencos, vendors, and consultants. Interested in joining up? It’s easy — just point your browser to www.prbcoals.com and click on "Membership."

Among the benefits that membership affords are the chance to share lessons learned with your peers and the opportunity to join a subcommittee dealing with an issue dear to your heart (electrical classifications, fire protection and risk management, fuel handling, or boiler performance and combustion, to name just a few).

The PRBCUG’s web site is your one-stop source for all things PRB. It was recently redesigned and augmented with tons (pun intended) of valuable and exclusive information — including a constantly updated database of plant consumption and a list of plants that are considering converting to PRB coal.