This research explores the techno-economic potential for a predominantly renewable electricity-based microgrid serving an industrial-sized drink water plant in the Netherlands. Grid-connected and stand-alone microgrid scenarios were modeled, utilizing measured wind speed and solar irradiation data, real time manufacturer data for technology components, and a bottom-up approach to model a flexible demand from demand response. The modeled results show that there is a very high potential for renewable electricity at the site, which can make this drink water treatment plant’s electricity consumption between 70% and 96% self-sufficient with renewable electricity from solar PV and wind power production. The results show that wind production potential is very high onsite and can meet 82% of onsite demand without adding solar PV. However, PV production potential is also substantial and provides a more balanced supply which can supply electricity at times when wind production is insufficient. Due to the supplemental supply over different parts of the day, adding solar PV also increases the benefits gained from the demand response strategy. Therefore, a solar–wind system combination is recommended over a wind only system. A 100% renewable system would require extremely large battery storage, which is not currently cost effective. Ultimately, even at the low wholesale electricity and sell-back price for large electricity consumers, grid-connection and the ability to trade excess electricity is extremely important for the cost-effectiveness of a microgrid system.