Renewable Thermal Energy Systems: Modeling Developments and Future Directions (Report 3)

Abstract

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Renewable Thermal Energy Systems: Systemic Challenges and Transformational Policies (Report 2)

“…The third report in this RTES series, Renewable Thermal Energy Systems: Modeling Developments and Future Directions (Report 3), demonstrates through case studies the improvements to simulation and techno-economic analysis of hybrid RTES (Akar et al 2023). This is a fundamental piece of providing information about their techno-economic performance.…”

Renewable Thermal Energy Systems: Characterization of the Most Important Thermal Energy Applications in Buildings and Industry (Report 1)

“…Another important operational hybrid RTES solution for district heating (which could also have higher temperature applications), is the hybrid district heating plant at Marstal in Denmark. Denmark has enabling policies for the use of solar thermal and RTES for district heating, coupled with the high costs of natural gas (Akar et al 2023;McMillan et al 2023). This example was chosen to highlight another operating hybrid RTES configuration in the colder northern latitudes, which is similar to the U.S. Northeast.…”

“…• Obtaining or estimating cost information regarding RTES options (e.g., the costs of heat pumps and different collectors in the U.S. market) • Further analysis of RTES hybrid options and their modeling (see Report 3 in this series [Akar et al 2023]) • Detailed heat demands for specific types of buildings (e.g., temporal and seasonal variation of heating loads for specific buildings) o Utilizing ComStock to investigate prototype building heat loads/demand profiles • Further review of policies and business models for RTES for industry in the United States o See Report 2 in this series (McMillan et al 2023) for initial work o Further review and evaluation of examples of policies and business models being used globally could be utilized in U.S. conditions • Further analysis to disaggregate water heating technologies for buildings and therefore to determine hybrid RTES suitability • Detailed heating demands by region that could be met by district heating systems o A case study for the application of heat pumps for a district energy system was explored in the Solar World Congress 2021 paper (Akar et al 2021) • Detailed analysis of industrial processes and temperatures, particularly at less than 300°C, to allow for suitable matching to potential RTES and hybrid RTES solutions o This includes updated temperatures and thermal profiles of selected industries that include temporal estimation of the process • Upgrades to the System Advisor Model or the use of tools like TRNSYS: o Load profiles that can be selected by the user representing various industries, or allowing the user to input their own time-varying heat demand profile o PV and heat pumps coupled together; modeling of other select PV and heat generation technologies identified in this report, such as PV and resistive heating o Further RTES components and technologies modeled to form hybrid RTES options  See Report 3 in this series (Akar et al 2023) where (1) flat plate collectors and parabolic trough collectors and (2) direct steam generation linear Fresnel collectors coupled with phase change material storage were co-modeled o Hydrogen or ammonia burners  Initial analysis was undertaken for hydrogen mixed with natural gas  Hydrogen burners operating on 100% hydrogen were not modeled • Proposed decision support tool is under initial development o See Report 3 in this series (Akar et al 2023) for discussion of a future decision support tool for highlighting the value of RTES (either in stand-alone or hybrid configuration) for IPH needs o Gaps can be further determined through workshops with decision makers, national labs, and industrial end users that could benefit from such a tool.…”