Energy and Exergy Analysis of a Modified Absorption Heat Pump (MAHP) to Produce Electrical Energy and Revaluated Heat

The novel modified absorption heat pump (MAHP) with the H2O-LiBr working mixture for cogeneration applications is introduced. The MAHP can simultaneously produce electric energy and heat revaluation. The proposed system has the particularity that it can be powered by alternative thermal sources (such as solar energy, biomass, geothermal) or industrial waste heat, thus promoting the production and efficient use of clean energy. The effects of pressure ratio (RP), source or supply temperature (T-GH), and the energy revaluation gradient (GTL) are analyzed. The critical parameters of the proposed system are evaluated, including thermal efficiency (eta(Th)), exergetic efficiency (eta(Ex)), revaluated heat ((Q) over dot(A)), as well as net power produced ((W) over dot(net)). For the MAHP analysis, RP and T-GH operating ranges were chosen at 1.1-15.0 and 100-160 degrees C, respectively. The results show that eta(Ex) of 87% can be obtained, having the maximum performance in T(GH )of 120 degrees C, RP of 1.1, and GTL of 35 degrees C. The eta(Th )varies between 51% and 55%, having a maximum GTL of 45 degrees C. On the other hand, (W) over dot(net )achieves values between 260 and 582 kW, depending on the defined operating conditions.

Automated summary

The novel modified absorption heat pump (MAHP) with the H2O-LiBr working mixture for cogeneration applications is introduced in this paper. The system has the particularity that it allows power supply from alternative thermal sources or industrial waste heat, promoting the production and efficient use of clean energy. The effects of pressure ratio, source or supply temperature, and energy revaluation gradient are analyzed, and the critical parameters of the proposed system, such as thermal efficiency, exergetic efficiency, revaluated heat, and net power produced, are evaluated. The results show that the system can achieve high exergetic efficiency and varied thermal efficiency and net power depending on the operating conditions.