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Title: Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel

The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO 2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables to 20%, all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO 2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required bymore » the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m 2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore, the results obtained with DER-CAM illustrate the complexity of interactions between DER and passive measure options, showcasing the need for a holistic optimization approach to effectively optimize energy costs and CO 2 emissions. Lastly, the simultaneous optimization of building shell improvements and DER investments enables building owners to take one step further towards nearly zero energy buildings (nZEB) or nearly zero carbon emission buildings (nZCEB), and therefore support the 20/20/20 goals.« less
 [1] ;  [1] ;  [2] ;  [3]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Center for Energy and innovative Technologies (CET), Doberggasse, Hofamt Priel (Austria)
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Inst. of Superior Tecnico (IST), Lisbon (Portugal)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0306-2619
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Applied Energy
Additional Journal Information:
Journal Volume: 132; Journal Issue: C; Journal ID: ISSN 0306-2619
Research Org:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Electricity Delivery and Energy Reliability (OE)
Country of Publication:
United States
25 ENERGY STORAGE; 54 ENVIRONMENTAL SCIENCES; 99 GENERAL AND MISCELLANEOUS; Building retrofits; Distributed energy resources; Microgrid; Mixed integer linear programming; Strategic decision; Zero net energy buildings
OSTI Identifier: