Radically Reducing the Cost of Solar Water Heaters

Wednesday, April 17th: 3:15-4:45 PM

Authors: Jay Burch, Jeff Maguire, Kristen Ardani
Presenter: Jay Burch, BS, PhD, Residential Buildings, National Renewable Energy Laboratory, Golden, Colorado

Abstract:  Currently, solar water heaters (SWHS) cost $4,000 to $12,000, depending on many factors. Many analysts have concluded that such costs are too high for SWHS to have a significant share of the U.S. market. The first talk lays out the rationale behind the ultra-low cost goals adopted by the Department of Energy ($1k-$3k), and updates two low-cost projects presented at ASES 2012: polymer thin film and evacuated tube thermosiphon systems. The next talk focuses on an emerging strong competitor to SWHS: heat pump water heaters (HPWHS). HPWHS cost $1.5 – $3k and save energy comparably to SWHS. They also provide cooling, mostly useful in warm climates and mostly detrimental in cold climates. Solar will have to cede the electric market in warm climates to HPWHS unless their costs and savings are comparable. The next talk discusses SWH soft costs (permitting/inspections, marketing, distribution, high overheads), which can be as large as half the cost of a SWH. On-going work to reduce these costs is noted, but success depends on non-engineering structural changes. The last two talks present inspiring innovative ultra-low-cost SWHS developed in the crucible of the DIY community.