A Path to Fuel and CO2 Reductions

Power Generators continue to find themselves needing to pace with decarbonization while meeting the growing market demand. One way to best solve both challenges is to drive efficiency of plant operations. Operations Performance Management solutions can help power generators ensure that their plant is operating at expected performance.

Quantifying CO2 emissions

Heat rate is the power industry standard for quantifying the fuel efficiency of the overall power system expressed in units of fuel per unit mw generated. Heat rate is the inverse of efficiency.

Take for example, a combined cycle power plant with a gross efficiency of 60% that has a gross heat rate of 5,700 btu/kwh. In this case, assuming the same quantity of mw generation, a 1% reduction in heat rate equates to a 1% reduction in emissions. Fundamentally, the amount of raw fuel input and combustion byproduct output (CO2, CO, NOx…) are related. Regulators often quantify the amount of (CO2) emissions from energy production (and generation emissions costs) by using production fuel quantities as a direct proxy.

Plant operators need to focus on safe and reliable generation meeting their dispatch commitments, equipment degradation performance recovery is difficult and expensive to identify and quantify. Heat rate is a moving target changing with load, operating mode, environment, process and equipment condition. Heat rate is not a direct measurement. Heat rate is a business and environmental initiative.

Heat rate performance

Combined cycle power systems utilize a complex set of equipment including fuel systems, turbines, heat exchangers, pumps, etc. All of the associated equipment is used to achieve the power system's overall power generation targets at the best achievable heat rate based on the plant and equipment design. Any changes or degradation in the equipment-level performance has an associated impact on the overall plant heat rate. For example, if a heat exchanger becomes blocked/clogged or has fouling on the tubes, its heat transfer efficiency goes down, and in turn the overall system efficiency goes down with a resulting increase in the overall plant fuel consumption required for the same quantity of MW output generation.

Plants operate across a wide range of operating loads and a variety of equipment configurations to achieve the desired load or dispatch targets. Each of these loads and operating modes has an associated heat rate entitlement.

Measuring, monitoring, diagnosing and quantifying heat rate performance at the overall plant level and across the plant system of equipment is a challenging and expensive task for power generation operators. For many, a dedicated staff of thermal performance engineers are tasked with pouring through reams of sensor data, and distilling it down into meaningful insights regarding the equipment performance and business priorities for O&M/outage planning. Power generation operators also use performance monitoring software to aid plant support personnel and management teams to improve effectiveness and productivity in heat rate monitoring and management.

Digitize for operational performance

Operations performance management software, such as GE Digital's OPM software application, helps power generators optimize operational performance. Specifically, OPM can help:

• Reduce/maintain operating emissions: Monitor and detect performance issues driving system inefficiencies and increasing fuel burn and emissions required to achieve dispatch targets.

• Reduce/maintain annual fuel cost: Plant and equipment performance data and automated alerts and diagnostic advisors help ensure plant is operating at its performance entitlement across the load range.

In addition, Operations Performance Management can help power generators increase revenue and margins with visibility and insight such as:

• Improve/maintain operating capacity: Analytic tools help users understand degradation levels and impact on overall plant performance, economic impacts and improved O&M decision making.

• Reduce/maintain plant turndown: Operating mode analytics provide insights to ensure minimum load operations are at expected levels and insights into limitations.

• Reduce/maintain start time and fuel cost: Start event analytics provide gross start performance and start profile details enabling users to ensure the start process meets expectations with visibility into sources of variation.

• Increased staff productivity: Automated performance analysis and tools enable staff to be more effective operating with high-quality advanced analytic outputs and advice so they can focus on high-priority items.

Using power system engineering expertise and advanced analytics, Operations Performance Management drives operational and thermal performance improvement, helping power generators reduce their CO2 footprint while enhancing revenues and meeting today's power demands.

Looking for more insights on how you can drive further plant operational efficiency?  Look at GE Digital's Operational Performance Management solutions for Power Generation.