Unique Tracking Number Assigned by MORTS ______
RESEARCH TOPIC ACCEPTANCE REQUEST (RTAR) FORM
Sponsoring TC/TG/MTG/SSPC/EHC/REF: ____TC6.7______
Title:
Solar Domestic Hot Water (SDHW) system modeling procedure.
Applicability to ASHRAE Research Strategic Plan:
This research will contribute to ASHRAE Research Strategic Plan 2010-15 goals 1, 2, 3, 5, 6, 7, 9, and 10 by improving the performance evaluation of SDHW systems. This procedure could be used to create an ASHRAE standard for evaluating SDHW systems that makes it easier to compare and select different kind of SDHW system for different uses and climates. Net zero energy buildings can not be achieved without Solar energy and other renewable energy sources and as net zero energy buildings become more common, SDHW systems are going to be more common in new building projects.
Research Classification:
Applied Research
TC/TG/MTG/SSPC Vote: Reasons for Negative Votes and Abstentions:
(For –Against-Abstentions-Absent-Total) (Negative Votes)
(Abstentions)
Estimated Cost: Estimated Duration:
$30,000 12 months
RTAR Lead Author Expected Work Statement Lead Author
Svein Morner, Svein Morner,
Co-sponsoring TC/TG/MTG/SSPCs and votes:
None
Possible Co-funding Organizations:
IAPMO, Adam Muliawan,
Application of Results:
The result of this research can be used to create an ASHRAE standard for evaluating solar systems through simulations.
State-of-the-Art (Background):
The OG-300 is currently used by Solar Rating Certification Corporation (SRCC) to rate SDHW systems. SRCC’s rating is used by utilities to provide incentives for renewable energy system. However, OG-300 does not describe the simulation evaluation process concisely enough that the results can be replicated by anyone else who attempts to evaluate the performance of the same solar system. Critical parameters such as the load profile, simulation timestep, initial conditions, baseline systems etc. are not defined at all or not well defined. The variation from two evaluation attempts of the same system can be in the range of 10-40% and possibly more depending on the assumptions and methodologies used.
Also, OG-300 contains significant amount of information that is irrelevant to the performance evaluation (pertains to the installation of the system) of the solar system making the process even more difficult to follow and understand. Other guidelines and standards describing the evaluation of SDHW systems also do not provide consistent results and leave many parameters and assumptions to the engineers (such as CSA F379 Series 09, EN 12976-2, ISO/DIS 9459-5:1997, …….).
Advancement to the State-of-the-Art:
The improvement of the procedure for evaluating SDHW systems will make it easier to objectively compare different kinds of SDHW systems hence increase the chance that the most beneficial SDHW system is selected. In addition, manufacturers and installers may be held to a higher standard when the conditions of the evaluation parameters are better defined. An estimated improved energy efficiency of the selected SDHW system could be in the range of 5% to 10%.
Justification and Value to ASHRAE:
As the ASHRAE energy efficiency requirements approach net zero energy buildings, a significant portion of the ASHRAE members will need to use SDHW systems for their buildings. As the use of SDHW system grows, so will the need to be able to reasonably quickly evaluate different types of systems in an objective, predictable and reliable manner. This is not currently available and ASHRAE could provide the standard for how to do this predictably and reliably. We estimated that 50% of ASHRAE members in the next 10 years will in some way be involved with evaluating SDHW system performance. ASHRAE could be the association publishing this standard.
Objectives:
The objective of this research is to identify and define the critical parameters associated with simulating SDHW systems performance. In addition, a procedure for the simulations needs to be defined such that different entities (and perhaps even different software) will end up with similar performance results.
Key References:
(List references cited in the state-of-the art section.)
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