Sunpower & Geyser

Option1: Solar geyser, direct heating of water and solar geyser.
Option2: Retrofit current geyser.
- Option2a: Add direct or indirect solar panel + controller + pump to circulate.
- Option2b: PV panel, with electric connection to current geyser.

Option2b: PV(Photo Voltaic) panels geyser retrofit

Highlevel.
1. PV panels 100w - 220w generate DC power 20v-70v DC at 1-10 Amps each.
2. Home power 220v (Not USA) AC
3. Geyser element Resistance = 220v^2/3000w = +- 16ohms for 3kW element.
Problem, is we cant just connect 220v AC and 50v DC in paralell as this would probably damame panel and push DC voltage into home electricity.
Solutions:
1. Dual elements - use one for AC and one for DC http://waterheatertimer.org/How-to-wire-water-heater-thermostats.html
2. Some complicated electric circuit with AC/DC filters.
3. Electronic control with 3way relay. A.220v, B.50v DC, C.off only one at a time.

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