Get a programmable thermostat for your water heater = turn the temps down an hour or two after you go to bed, or during the warmer times of the day, or the times when you typically don’t use your hot water. No reason to heat what is not being used!
Over the last 30 years, we have seen solar energy prices drop dramatically. The National Renewable Energy Laboratory of the U.S. Department of Energy has reported solar photovoltaic price trends since 1980. Their records show that the price per Watt of solar modules has dropped, on average, from $22 to under $3 in the last 30 years.