Review of Various Forms of Exergy and Allocation of Consumptions in Cogeneration - Lecture 10

Overview

Explore advanced thermodynamics concepts in this MIT lecture focusing on various forms of exergy and allocation challenges in cogeneration systems. Delve into detailed examinations of exergy in bulk flow interactions, heating and cooling processes, and hydraulic jumps. Master the principles of log-mean temperature calculations and minimum exergy requirements for low-temperature heating applications. Study the exergy associated with fossil fuels, including heating values and the evolution of fuel-to-power conversion technologies. Examine critical allocation issues in Combined Heat and Power (CHP) systems, including methodologies for determining fuel consumption, primary energy savings, and reference efficiency values. Learn about allocation challenges in hybrid facilities and various approaches to solving these complex energy distribution problems. The lecture, recommended to be viewed at 1.5x speed for optimal learning, includes comprehensive examples and practical applications of these advanced thermodynamic concepts.

Syllabus

- Introduction
- Exergies and Efficiencies in Energy Conversion
- Exergy of Bulk Flow Interactions
- Exergy in Heating and Cooling Bulk Flows
- Exergy of an Hydraulic Jump
- Log-Mean Temperature in Heating/Cooling a Flow
- Minimum Exergy for Low Temperature Heating
- Exergy Associated with a Fossil Fuel
- Lower Heating Values of Some Fuels
- The Learning Curve of Fuel-to-Power Conversion
- Beyond Flame-Based Fuel-to-Power Conversion
- Avoiding the Inherent Irreversibility of Flames
- Allocation Issues in Combined Heat and Power CHP
- How Much Fuel Is Consumed to Produce Heat in CHP?
- Allocation Fractions and Primary Energy Savings
- Incremental Electricity-Centered Allocation in CHP
- Separate Production Reference Allocation in CHP
- Choice of Reference Efficiencies
- “Fair” Reference Values in a Given Local Area
- Allocation Example in CHP: Methods Compared
- Allocation Problem in Hybrid Facilities
- Allocation Fractions and Primary Energy Savings
- Incremental Fossil-Centered Allocation
- Separate Production Reference Allocation
- Choice of Reference Efficiencies