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In proposing the wide-reaching Clean Power Plan, the U.S. Environmental Protection Agency (EPA) has laid out four key “building blocks” that states can use to develop their implementation plans. One of those buildings blocks focuses on improving the heat rate – that is, fuel efficiency – of coal-fired power plants. Utility executives from across the country gathered at a Black & Veatch-sponsored forum to discuss how to accomplish improving heat rates, as well as share reaction to the Clean Power Plan.

The Greenhouse Gas Strategies Forum, held in Kansas City, Missouri, attracted nearly 100 people, including utility executives, industry leaders and government regulatory personnel. Sessions during the two-day event covered many aspects of the Clean Power Plan, including legal issues, operations for renewables,combustion turbines and nuclear plants, the outlook for carbon capture and sequestration, and more. The forum concluded with a panel discussion of leading experts in the field.

The building block for energy efficiency focuses on a 6 percent target for heat rate improvement at existing coal-fired facilities. David Brill, Asset Management and Energy Efficiency Program Manager for Black & Veatch, said reaching such a target could be difficult for some, for a variety of reasons, but he cautioned against letting that number stop plant owners from implementing needed improvements.

“In general, this is an opportunity to do what’s good for the health of the plant, its performance and reliability, and to solve any chronic problems you may be experiencing,” Brill said.

Over the past 15 years, power generation companies have been consistently investing in assets to make them more efficient, but there are a limited number of “big-ticket” items that can make a major impact. The Clean Power Plan establishes the benchmark year as 2012, so any improvement completed during that year or before will not count.

“For those that have already completed the larger efficiency updates, the idea that you’re going to get another 6 percent on top of that is pretty optimistic,” Brill noted. In addition, EPA is gauging overall goals based on statewide levels, not individual plant performance.

“You’re not going to use heat rate as your only objective, anyway,” Brill said. “You should establish goals that encompass all things related to the plant. But don’t think everything has to be a capital improvement. There’s a lot of opportunity in many cases on the operation side.”

He said another hurdle holding some plant owners back from investing in heat rate improvements is the threat of New Source Review (NSR) from EPA if any of the improvements were to significantly change the operational profile of the plant. An NSR could effectively tell a utility that if it proceeds with the improvement, the company may also have to upgrade or install new air quality control technology.

“There’s always a ‘gotcha’ from layered regulations,” Brill said. “If you haven’t done a major steam turbine upgrade, you likely haven’t done it for one reason – the threat of NSR.”

While that is a tough hurdle, he said plant owners can’t sit back and just wait – doing nothing. “Owners should at least do a study to determine the risks and opportunities. That would be an appropriate step at this stage. Do a high level review, screen the viabilities and then evaluate.”

EPA has stated that the NSR issue has generated a substantial amount of commentaries during the Clean Power Plan comment period, and it might be an area of flexibility once the plan is finalized.

Capital Improvements

There are many types of capital improvements that plant owners can undertake, and Black & Veatch has conducted scores of feasibility studies for heat rate improvements. Brill said steam turbine upgrades top the list, because they yield the biggest improvement in heat rate, but they are also among the most expensive. “Owners should make project upgrades because they make sense economically and they yield significant improvements in efficiency,” Brill said. “But if you’ve done a steam turbine upgrade in recent years, the opportunity for heat rate improvement is greatly diminished.”

Second on the list is cooling tower rebuilds. Many 30-year-old wooden towers are at the end of their useful life. “It’s also an opportunity to optimize the tower size to make systems more efficient.”

Other equipment upgrades that can improve the heat efficiency rate is intelligent soot blowing, condenser retubing, condenser ball cleaning systems, and modifications to air heater systems to improve heat transfer and reduce leakage, among others.

Brill said many coal-fired plants are considering partial or full conversion to natural gas. He noted that owners need to be aware that if they are considering full conversion, they may be required by EPA to decommission all coal handling and feed equipment, so the option of running on coal in the future, even partially, would not be possible.

Operational Improvements

Scott Stallard, Asset Management and Strategic Integrated Infrastructure Director for Black & Veatch, pointed toward two key trends that may have an impact on heat rate calculations. First, units that formerly were used for baseload may not be baseload in the future, and the shortened nature of their usage will also cut their heat rate. Secondly, he noted that some plants are switching back to Eastern U.S. coal, now that many have completed air quality control upgrades. This could help improve operations as the Eastern coals are higher in energy content, lower in moisture, and the fuel type most facilities were designed for.

Stallard said plant managers should have operational targets to shoot for. “If you don’t have tightly defined targets, it will introduce bias into the equation. Therefore, you have to understand the causal factors in order to demystify what you can control and what elements are beyond your control.”

Owners should have a broad viewpoint in evaluating plant operations, including heat rate, performance, cost management, operational risk and reliability. “Managers should integrate all of these, not view each as an independent island,” Stallard said. This ‘360 degree view of the problem’ should examine fuel quality impacts, maintenance, operations strategies and proper diagnostics.

But managing a plant’s heat rate is something owners have to stay on top of continually, he said. “You can’t be casual about it. It takes constant attention.”

Stallard said one way of getting a handle on plant efficiency and operation is through monitoring and diagnostics (M&D). “In our M&D services, we are looking for divergences or anomalies, which can be based on data patterns that can be challenging to detect to the human eye,” Stallard said.

M&D stands out as a way of identifying emerging issues early so as to mitigate their impact. With Black & Veatch’s M&D operations based both in the U.S. and India, power plants can be monitored 24/7.

But Stallard said early detection of issues using sensors and measurement tools is only the beginning. “Plant owners also must focus on reliability and efficiency. Ask yourself, ‘How often can I look at my data?’ You really want to keep score – you want to measure yourself so the process improves itself.”

Through this, a plant can establish benchmarks, then make calculated targets for improvements, Stallard said.

The four building blocks offered by EPA give states some direction for meeting the overall targets outlined in the Clean Power Plan, Stallard said. Owners should be actively working now toward developing assessments, solutions and implementation plans.

Published originally on Black & Veatch Solutions.