I'm not sure If anyone is still interested, but I'm a Grad student in Architecture and we built a house last year for a competition (The Solar Decathlon) and it ran off nothing but solar for everything! We used vacuum tubes for our solar hot water. We ran showers, dishwasher, and any hot water for cooking (as determined as average use by the competition) consecutively for 5 days during the competition. We never once ran out of hot water. We had an electric backup hot water heater but only had to use it initially the first day to bring the water temp up for the first run, but that was it.
You may be able to find some useful information through the competition website (all the manufactures should be listed). Or this solar technologies website.
http://www.solardecathlon.org/
http://www.thermomax.com/index.php
From my limited but thorough experience the vacuum tubes can't be beat. They are much more efficient and can insure heat even through winter! In combination with a wood pellet boiler could be a deadly and cost effective system. It's claimed that vacuum tubes on a well insulated house can pay for itself in 3 to 7 years.