Here we design, construct, and characterize a compact Raman-spectroscopy-based sensor that measures the concentration of a water-methanol mixture. The sensor measures the concentration with an accuracy of 0.5% and a precision of 0.2% with a 1 second measuring time. With longer measurement times, the precision reaches as low as 0.006%. We characterize the long-term stability of the instrument over an 11-day period of constant measurement, and confirm that systematic drifts are on the level of 0.02%. We describe methods to improve the sensor performance, providing a path towards accurate, precise, and reliable concentration measurements in harsh environments. This sensor should be adaptable to other water-alcohol mixtures, or other small-molecule liquid mixtures.

A modeling architecture is presented to better understand the value of thermos-mechanical system with agility: the ability to provide an uninterrupted service to a customer while simultaneously adjusting their own energy consumption based on price signals. The results of this modeling show a significant opportunity for devices with increased thermal agility to provide both financial and environmental benefits to customers who adopt them. Systems with multiple hours of agility either via storage, advanced controls, fuel switching, or other means could decrease utility costs by up to 50%.