A solar panel can in most cases last 20 to 30 years if it's maintained properly and kept clean.
Some solar panels may last longer than 30 years but they sometimes lose their ability to efficiently produce over as time goes on and may need to be replaced.
Solar energy is cheap to operate although solar energy can be expensive to install and purchase all the needed equipment.
You not only need the solar panels but you also need battery banks for storage of the solar power as well as an inverter to convert the DC to AC power to operate your 110 to 220 volt electrical appliances and electronics etc.
The actual cost of the solar panels and inverters and batteries will depend on how many solar panels you need, how many batteries you need and the size of inverter you need.
The more power you need from the solar panels the more expensive it will be.
However solar panels have gone down in price since they first came out but they can still be expensive if you want a large solar panel setup.
In some cases you may be able to recoup the cost of the solar panels and equipment over time depending your electricity rates and how much electricity you use but for some people they may never recoup the cost.
Solar and wind energy are renewable energy sources that have low operating costs which are even lower than fossil fuels such as oil, natural gas, coal etc.
However installing solar panels and wind generators can be expensive, especially when you need to install a huge solar farm or install large wind turbines.
For homes you would need to install a lot of solar panels as well if using solar energy along with the battery banks and inverters that can raise the cost into thousands of dollars which can take over a decade or longer to pay back.
However for small solar panel setups the cost can be recovered pretty quickly and you can use solar part time and use your normal electricity when you need more power.
Also improved efficiency of solar panels and wind turbines, along with the competition among renewable energy providers have also lead to lower costs.
Natural gas for electricity generation is sometimes cheaper in some areas for a power plant to operate steam turbine generators and in other places the coal can be cheaper to burn to make steam to power the steam turbine generators.
We still do need natural gas and coal power plants as well as nuclear power plants because solar panels and wind turbines cannot provide the entire world with enough power.
And solar only works when the sun is shining and wind turbines only work when the wind is blowing enough to spin the wind turbines.