Characterization of Storage Sizing for an Off-Grid House in the US and the Netherlands

Abstract

This work uses experimental data to estimate the size of storage needed for an isolated off-grid household in two different regions (Austin, Texas, US, and Nunspeet, NL). In our study, an off-grid house is considered to be supplied with 100% renewable energy during the summer period, in which cooling demand is neglected, and a solar photovoltaic (PV) system and batteries are the main electrical energy providers. Based on results achieved with the DEMkit simulation package we can conclude that, in both cases, using a solar PV system and a Sea-Salt battery would have been sufficient to provide the necessary electricity without showing a blackout during the summer of 2016. The Austin household needs a solar PV system of 38 kWp and storage of 452 kWh; in the case of Nunspeet, a solar PV system of 11.5 kWp and storage of 90 kWh is sufficient. Furthermore, using the DEMkit model, it is possible to determine an optimal value for the size of storage to half of the initial battery capacity (226 kWh for Austin and 45 kWh for Nunspeet) and still be able to provide enough power to cover the load demand of the households during the summer. In a second part, data of the solar PV system and load from Austin for one specific week was used to create data of a 'typical' but downscaled day. This day was used to determine the fluctuation of electricity for a real Sea-Salt battery for the considered off-grid scenario in Austin. The downscaling of the data was needed in order to have load values that fit to the size of the real battery. The tests show that the Sea-Salt battery under real electricity fluctuations is possibly adequate for off-grid scenarios.

Energy Storage Sizing Optimization and Sensitivity Analysis Based on Wind Power Forecast Error Compensation

“…The upper and lower bound of the confidence intervals are written as (eαlow eαup). Here, we suppose the error obeys the normal distribution which is used commonly [22][23][24][25][26]. The method in this paper is applicable for both normal distribution and other distributions.…”

“…Based on the historical forecast error of wind farm, the distribution law of the error was analyzed. As we did not focus on the error distribution in this paper, the assumption was that the error obeys the normal distribution which is most widely accepted by most researchers [18,[22][23][24][25][26]. This method was also compatible for other distributions.…”

Smart Appliances for Efficient Integration of Solar Energy: A Dutch Case Study of a Residential Smart Grid Pilot

“…Daily and seasonable meteorological conditions significantly affect renewable energy production [3] as well as demand patterns. 100% matching of the residential consumption with renewable energy can be achieved by PV systems in combination with residential storage systems such as batteries [4,5], vehicle to grid technologies [6], or by using community-based storage systems [7]. Although batteries may be required to maintain a high quality of the power fed into local electricity networks, alternative solutions for the realization of flexibility may need to be evaluated because of the high environmental impact of batteries [8].…”

Energy Storage Technologies for Off-grid Houses

“…Batteries are an appealing technology that can be used as storage technology for managing the mismatch between generation and consumption in buildings and houses [40][41][42]. Furthermore, recent advances in halide carbon based battery technologies have increased the potential for using this technology in off-grid houses [35]. The combination of renewable energy with these new batteries for usage within microgrids is studied at the University of Twente in the Netherlands [38,43,44].…”

“…It has been developed in the Netherlands by the company Dr Ten BV [34]. The battery is currently under test in the Netherlands, USA, Belgium and Israel and it is expected that the battery will be on the market by 2022 [20] [35]. This battery has also been used in research of our group at University of Twente for use in smart grids [35] [36].…”