Solar energy capacity is continuing to increase. The key challenge with integrating solar into buildings and the electric grid is its high power generation variability, which is a function of many factors, including a site's location, time, weather, and numerous physical attributes. There has been significant prior work on solar performance modeling and forecasting that infers a site's current and future solar generation based on these factors. Accurate solar performance models and forecasts are also a pre-requisite for conducting a wide range of building and grid energy-efficiency research. Unfortunately, much of the prior work is not accessible to researchers, either because it has not been released as open source, is time-consuming to re-implement, or requires access to proprietary data sources. To address the problem, we present Solar-TK, a data-driven toolkit for solar performance modeling and forecasting that is simple, extensible, and publicly accessible. Solar-TK's simple approach models and forecasts a site's solar output given only its location and a small amount of historical generation data. Solar-TK's extensible design includes a small collection of independent modules that connect together to implement basic modeling and forecasting, while also enabling users to implement new energy analytics. We plan to release Solar-TK as open source to enable research that requires realistic solar models and forecasts, and to serve as a baseline for comparing new solar modeling and forecasting techniques. We compare Solar-TK's simple approach with PVlib and show that it yields comparable accuracy. We present three case studies showing how Solar-TK can advance energy-efficiency research.
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Weatherman: Exposing weather-based privacy threats in big energy data
Smart energy meters record electricity consumption and generation at fine-grained intervals, and are among the most widely deployed sensors in the world. Energy data embeds detailed information about a building's energy-efficiency, as well as the behavior of its occupants, which academia and industry are actively working to extract. In many cases, either inadvertently or by design, these third-parties only have access to anonymous energy data without an associated location. The location of energy data is highly useful and highly sensitive information: it can provide important contextual information to improve big data analytics or interpret their results, but it can also enable third-parties to link private behavior derived from energy data with a particular location. In this paper, we present Weatherman, which leverages a suite of analytics techniques to localize the source of anonymous energy data. Our key insight is that energy consumption data, as well as wind and solar generation data, largely correlates with weather, e.g., temperature, wind speed, and cloud cover, and that every location on Earth has a distinct weather signature that uniquely identifies it. Weatherman represents a serious privacy threat, but also a potentially useful tool for researchers working with anonymous smart meter data. We evaluate Weatherman's potential in both areas by localizing data from over one hundred smart meters using a weather database that includes data from over 35,000 locations. Our results show that Weatherman localizes coarse (one-hour resolution) energy consumption, wind, and solar data to within 16.68km, 9.84km, and 5.12km, respectively, on average, which is more accurate using much coarser resolution data than prior work on localizing only anonymous solar data using solar signatures.
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- NSF-PAR ID:
- 10062543
- Date Published:
- Journal Name:
- IEEE International Conference on Big Data
- Page Range / eLocation ID:
- 1079 to 1086
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/BigData.2017.8258032
