Advantages and disadvantages of solar power

Advantages
The 89 petawatts of sunlight reaching the earth's surface is plentiful compared to the 15 terawatts of average power consumed by humans. Additionally, solar electric generation has the highest power density (global mean of 170 W/m2) among renewable energies.
Solar power is pollution free during use. Production end wastes and emissions are manageable using existing pollution controls. End-of-use recycling technologies are under development.
Facilities can operate with little maintenance or intervention after initial setup. Solar electric generation is economically competitive where grid connection or fuel transport is difficult, costly or impossible. Examples include satellites, island communities, remote locations and ocean vessels.

When grid connected, solar electric generation can displace the highest cost electricity during times of peak demand (in most climatic regions), can reduce grid loading, and can eliminate the need for local battery power for use in times of darkness and high local demand; such application is encouraged by net metering. Time-of-use net metering can be highly favorable to small photovoltaic systems.
Grid connected solar electricity can be used locally thus minimizing transmission/distribution losses (approximately 7.2%).

Once the initial capital cost of building a solar power plant has been spent, operating costs are low when compared to existing power technologies.).
Financially speaking, there are rebate advantages if you live in a state that offers rebates such as California, New York, New Jersey, and Arizona.

Disadvantages
Solar electricity is expensive compared to grid electricity.

Limited power density: Average daily insolation in the contiguous U.S. is 3-9 kW·h/m2 usable by 7-17.7% efficient solar panels.
To get enough energy for larger applications, a large number of photovoltaic cells is needed. This increases the cost of the technology and requires a large plot of land.
Like electricity from nuclear or fossil fuel plants, it can only realistically be used to power transport vehicles by converting light energy into another form of stored energy (e.g. battery stored electricity or by electrolysing water to produce hydrogen) suitable for transport.
Solar cells produce DC which must be converted to AC when used in currently existing distribution grids. This incurs an energy loss of 4-12%.

Availability of solar energy
There is no shortage of solar-derived energy on Earth. Indeed the storages and flows of energy on the planet are very large relative to human needs.
The amount of solar energy intercepted by the Earth every minute is greater than the amount of energy the world uses in fossil fuels each year.
Tropical oceans absorb 560 trillion gigajoules (GJ) of solar energy each year, equivalent to 1,600 times the world’s annual energy use.
The energy in the winds that blow across the United States each year could produce more than 16 billion GJ of electricity—more than one and one-half times the electricity consumed in the United States in 2000.

Annual photosynthesis by the vegetation in the United States is 50 billion GJ, equivalent to nearly 60% of the nation’s annual fossil fuel use.
Plants, on average, capture 0.1% of the solar energy reaching the Earth. The land area of the lower 48 United States intercepts 50 trillion GJ per year, equivalent to 500 times of the nation’s annual energy use. This energy is spread over 8 million square kilometers of land area, so that each square meter is exposed to 6.1 GJ per year. This results in potential biomass production of 6,100 GJ per square kilometer per year. Compared to the 0.1% efficiency of vegetation, roof installable amorphous silicon solar panels capture 8%-14% of the solar energy, while more expensive crystalline panels capture 14%-20%, and large scale desert mirror-concentrator heat engine based setups may capture up to 30-50%.

From wikipedia
"Alternative Energy"