Some interesting things this seapanels can do:
Solar heat water for showers, cooking & cleaning: Save hundreds on your utility bills. Perfect for vacation homes and camping
Distill bottle-quality water (automatic mode): Remove fluoride, arsenic, impurities and chemicals from city water and well water.
Distill up to 1.5 gallons of water per day for emergencies and disasters (manual mode): Turn ANY source of water into bottle-quality water, including ocean water, brackish water, contaminated well water, and standing ground water.
Always have 20-gallons of emergency water: Perfectly fresh and can't drain back to empty city water lines.
They almost look simple enough, that if you got one, you may be able to build yourself.