It's been done, but not without controversy. https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facili

It's been done, but not without controversy. https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility At home, it's suitable in warm climates but is more challenging in snowy / very cold regions. Generally speaking, converting to electricity then using an electric water heater is more efficient because there's much less insulating, heat loss, and piping that can leak and cause water damage.