In the United States, water heaters are the second highest source of energy usage in households. A wide variety of water heater configurations are available in the market, some of which have higher operating costs than other configurations. Although the most common systems utilize natural gas or electricity to heat water, the use of solar water heaters is becoming more widespread mainly due to the low operating costs associated with this technology. Common designs of solar water heaters include fiat-plate collectors and evacuated tubes with a heatpipe attached to an absorber fin. In general, copper is used for the fabrication of these collectors due to its excellent heat transfer properties. However, other thermal designs allow the use of alternative materials without loss of performance. This paper discusses the performance of an aluminum-based minichannel solar water heater under several weather conditions throughout a year. (C) 2014 Elsevier Ltd. All rights reserved.