New coal fired plants are poised to benefit from the adoption of advanced automation and digital bus-based technologies.
Bill Brownlee, Emerson Process Management, USA
Some observers remark that coal is making a comeback. In reality, however, the statistics show that it never really went away. Coal fired power generation accounts for 39 per cent of total electricity production worldwide.
A number of countries, including the USA, Germany, Poland, Australia, China and India, rely on coal power to a much higher degree, according to Roadmapping Coal’s Future, a recent report published by the International Energy Agency.
In fact, according to the latest figures available from the World Coal Institute, 78 per cent of the electricity generated in China and 69 per cent of India’s electricity is derived from coal.
Coal’s momentum had slowed in recent years, particularly in the USA, as power producers have diversified their portfolios, turning to alternative energy sources to satisfy the growing demand for electricity. Natural gas, in particular, gained ground until volatile pricing soured its once attractive economic proposition.
Now, the abundance and affordability of coal, combined with promising new clean coal technologies – most notably supercritical and ultra-supercritical technologies, as well as integrated gasification combined-cycle (IGCC) – have brought new coal projects to life the world over by optimizing efficiency and environmental performance. For new construction coal is once again king.
Fueled by growing populations, expanding industrial bases, and abundant coal reserves, China and India are among the nations turning to coal for a wave of new power plants already under construction, as well as those on the horizon. Coal is also a primary fuel source in the USA, accounting for roughly 50 per cent of net electricity generation. And yet, over the last 25 years or so, there has been little new coal fired plant construction.
Digital bus-based technologies provide actionable information that can help plant operators identify and correct potential problems before they pose problems that could culminate in costly unplanned outages
Today’s scenario points to a much different reality. In the USA, 154 proposed and new plants generating 93 GW of electricity – enough to power 93 million homes – are under consideration, according to Tracking New Coal Fired Power Plants from the US Department of Energy’s National Energy Technology Laboratory (NETL). A portion of these plants will replace existing facilities that are reaching the end of their service life, while others will meet the country’s growing demand for power.
Of course a lot has changed since the last group of coal fired plants were built three or more decades ago. Take the business climate as one example. Arguably, the restructuring of the electric power industry, which opened the market to competition, has had, and will continue to have, the most far-reaching implications for the USA’s power industry. Deregulation has spawned competitive markets operated by independent system operators (ISOs) and regional transmission organizations (RTOs) to control and manage the distribution of electricity over a particular geographic area. This, in turn, has made it necessary for power generators to operate more like traditional businesses focused on short and long term financial objectives.
Of course utilities in the USA are not alone in the need to adapt their business model. This scenario is also being played out in Europe, where the electricity market has been transformed from separate country-based monopolies to a more open, competitive environment that spans the continent.
While the industry is feeling pressure to keep a sharp eye on the bottom line, it is also faced with the mandate to comply with evolving environmental regulations. In fact, environmental compliance spending is expected to increase for the foreseeable future as power producers make significant capital expenditures in environmental technologies to meet current and proposed regulations.
Then there is the technology side of the equation. Because technology refuses to stand still, the majority of proposed plants will utilize technologies that did not exist when most current plants were built and commissioned. Just as wireless technologies are gaining momentum in the office and home (and are just now beginning to make their way into industrial settings as well), so too advanced automation and digital bus-based technologies are changing the way new coal fired plants are designed, constructed and operated.
Given today’s dynamic business, regulatory and competitive environment, power generators are finding it advantageous to embrace these technologies, which not only provide a sustainable operational foundation for the duration of the plant’s expected life, but also address today’s key industry drivers.
To illustrate this, consider the traditional power plant model with its mix of PLC and distributed control system platforms. Utilizing disparate systems result in separate islands of automation that are incapable of providing one comprehensive “snapshot” of all plant operations, and, furthermore, do not easily lend themselves to the ongoing incorporation of newer technologies across the board. This mixture also increases support costs because of differing spare parts and training needs.
Now contrast this short-sighted and rather limited approach to a streamlined, integrated plant-wide architecture that takes the best advantage of digital bus-based technologies. In this plant model, a single control system platform not only monitors and controls plant processes and equipment, but also captures important information from intelligent field devices and asset management software, resulting in unprecedented insight into plant operations and processes. Armed with this wealth of actionable information, plant operators are able to identify and correct potential problems – before they result in costly unplanned outages.
This digital bus-based approach to automation has already gained wide acceptance in other process industries, such as chemical, pulp and paper, and oil and gas, to name a few. Despite its successful track record, this approach is a major change on two separate fronts for the power industry.
First, because of the critical nature of the power generation process, the power industry has historically been slow to adopt new tactics and technologies that have a perceived risk to availability and reliability. Second, beyond the type of automation and control-related technologies ultimately installed, the digital bus-based approach can also directly impact the specification/procurement, construction, and start-up processes themselves.
You might say that in nearly every sense of the word, this is not your father’s coal plant.
An integrated plant-wide architecture incorporating digital bus-based technologies not only provides a sustainable operational foundation for a plant’s expected life, but also addresses today’s key industry drivers
As new coal plants increasingly advance from the drawing board to the construction site, a number of utilities have begun to use aspects of the PEpC (Procurement, Engineering, procurement, Construction) development/construction model, which facilitates reduced project duration and cost by engaging suppliers of critical equipment and systems early in the project.
This invaluable collaboration enables power generators to understand the impact that digital automation can have on both short term and long term profitability, and subsequently fully realize the operational and financial benefits of an integrated automation strategy.
With this approach, owners, developers and architect-engineering firms work alongside automation suppliers to jointly determine an automation foundation upfront, and define a set of automation design criteria. This early identification, specification and deployment of these automation technologies help power generators lower wiring costs and streamline device installation, communications verification and troubleshooting – an approach that translates into reduced start-up and commissioning costs. In fact, the integrated, intelligent and highly automated digital bus-based approach can lead to capital, construction and installation cost savings of up to $20 million for a typical 600 MW coal fired unit, according to The Economic Impact of Digital Bus Technology on New Plant Construction, a study conducted by JDI Contracts Inc. However, these savings can only be realized if the entire procurement, construction, and start-up work processes are modified to take advantage of this architecture.
But this is really just the tip of the iceberg. Power generators can continue to benefit as their plants experience long term operational and maintenance cost savings because of the efficiencies possible with a highly automated, intelligent plant. Utilization of intelligent instrumentation and asset management software can prevent forced outages by detecting and diagnosing potential equipment problems before they degenerate into major failures.
The implications of this predictive intelligence capability are significant, as the ability to potentially save two forced outages per year over 30 years can translate into savings of more than $8 million, according to the study. So, while initial investment in digital bus technology pays off during installation and start-up, the additional data that are delivered to the control system through the digital bus-based architecture pays dividends throughout the life of the plant.
With a wave of new coal plants expected to become operational over the next several years, the time to act is now. Increasingly, forward-thinking power generators are developing a strategic vision for how they can best leverage automation technologies not just today, but for years down the road. This vision is based on a careful evaluation of their automation options – not in a vacuum, but within the context of evolving operational, regulatory, environmental and economic climates.
The bottom line is clear. By making it possible to save millions of dollars while delivering a state-of-the-art plant, advanced automation and digital bus-based technologies are setting a new standard for plant construction and long-term operations and maintenance savings that puts power generators in the best position to thrive in an environment of competing resources, priorities and pressures.