Novel energy saving technologies for thermodynamic systems with carbon neutrality goal

• Published in: Energy reports Vol. 8; pp. 9541 - 9553
• Main Authors: Huang, Chang, Wang, Weiliang, Madonski, Rafal, Lyu, Junfu, Liu, Jizhen
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2022; Elsevier
• Subjects: Back pressure; Carbon neutrality; Efficient heat-supply technology; Energy conservation; Partial load; Steam governing optimization; Back pressure; Carbon neutrality; Energy conservation; Efficient heat-supply technology; Partial load; Steam governing optimization
• ISSN: 2352-4847; 2352-4847
• DOI: 10.1016/j.egyr.2022.07.059

To ensure carbon neutrality goal, coal-fired power plants will have to take responsibility of deep peak regulation, which is essential to the development of renewable energy power. The penalty for deep peak-regulating operation of coal-fired power units could be more than 40 g/kW h of the net coal consumption rate (NCCR), which is contracted to the adoption of renewable energy power. Hence, in order to identify promising energy saving directions, a distribution of exergy losses in thermodynamic systems of several typical large coal-fired power units is studied in this work. For reference, systematic investigations into related conventional energy saving technologies are conducted, which consider thermodynamic interactions among the components. As a result, three novel technologies are proposed to minimize the exergy loss of the units on the deep peak-shaving condition. Based on the performed feasibility study of these technologies, it is found that: (1) using novel steam governing method on the part-load conditions offers ∼5.5 g/kW h energy saving potential; (2) in the winter season, reducing the back pressure of a dry cooling unit from 15 to 4 kPa at partial load can reduce the NCCR by ∼15 g/kW h; and (3) adopting the efficient heat-supply technology based on pressure matching would provide a NCCR reduction potential of ∼6.2 g/kW h. These new solutions, due to their energy saving effect, positive environmental impact, and cost-effectiveness, forge a synergetic development path of coal-fired and renewable energy power generations under the carbon neutrality target. •The technological achievable energy conservation of power plants is discovered.•Technical route is proposed for coal-fired power plant to boost carbon neutrality.•Novel steam governing at partial load could potentially reduce NCCR by ∼5.5 g/kW h.•Novel ACC system could potentially reduce NCCR by ∼15 g/kW h in winter season.•Novel pressure-matching heat supplying method could reduce NCCR by ∼6.2 g/kW h.