In the past few years alone, the solar industry has gone from a clean energy source that required subsidies just to stay afloat to a full-fledged economic force. Solar energy is now passing grid parity in Europe, the southwestern U.S., South America, South Africa, and many other parts of the world. As costs fall, even more locations will find solar power to be economical, opening up a global electricity market worth over $1 trillion annually.

Here are just a few amazing statistics that show just how far solar energy has come and how big an opportunity it is for investors.

Solar is one of the fastest growing markets in the U.S. and a big provider of new jobs and new electrical generation. Image: SunPower. 

A global look at solar
To start, let's put the global solar industry in some perspective.

  • 37 GW: The number that global solar installations hit in 2013, according to the most recent data from Solarbuzz. That's enough to power over 6 million homes. 
  • 50 GW: How big the solar market is projected to be in 2014, 35% higher than last year.  
  • 12 GW: The amount of solar installed in China last year, followed by 9.5 GW in Japan, 4.4 GW in the U.S., and 3.3 GW in Germany.
  • 13.28 Euro cents/kW-hr: Germany's feed-in tariff rate for small rooftop systems, which is one-third of the average electricity cost for households of 29.2 Euro cents/kW-hr.
  • 9.19 Euro cents/kW-hr: Germany's feed-in tariff rate for large solar systems. 
  • 70 MW: The size of the largest merchant solar power plant (meaning the power will be sold to the grid at market prices) in the world, which SunPower (SPWR -2.21%) is building in Chile. The project will be 20% owned by the oil giant Total (TTE 1.72%), which also owns 66% of SunPower. 
  • 4 GW: The size of the solar project being planned in India, which would easily be the world's largest. Its estimated cost is $4.4 billion. 
  • $109 billion: The amount of money Saudi Arabia -- yes, the oil exporter -- plans to spend to meet its goal of a 100% renewable-energy future. The plan is beginning to take shape, starting with an expected 1 GW tender later this year. If that doesn't make oil companies nervous, I don't know what will.

SolarCity has brought solar to the masses, making the $0 down solar lease possible. Image: SolarCity.

A look at U.S. solar
The U.S. solar market has gone through many changes over the past decade and has been a political punching bag for years. But the industry now is at a sustainable cost structure, and even the pending reduction of the investment tax credit can't stop solar growth. Here's how far it's come in just a few years. (Note: Most of the following data is from the GTM Research/SEIA U.S. Solar Market Insights Report.)

  • 29%: The percentage of new electric capacity that installed solar accounted for in the U.S. in 2013, up from 10% a year before.
  • 41%: The growth in U.S. solar installations in 2013 to 4.75 GW.
  • 800,000: The number of homes that can be powered with the solar power installed in 2013 alone. 
  • $2.59: The per-watt weighted average cost to install solar power in the U.S. in Q4 2013, down 15% from a year earlier.
  • 34%: The amount residential solar installations have fallen in cost from Q1 2010 to Q4 2013 in the U.S., to $4.59 per watt.
  • 59%: The amount utility-scale solar projects have fallen in cost in the same timeframe, to $1.96 per watt. 
  • 55%: The percentage of of all U.S. residential solar installed in California in Q4, up from 43% in Q1 of 2010. No doubt, California dominates solar. 
  • 142,698: The number of people employed in the solar industry as of last November, up 19.9% from a year earlier, or 10 times the national average growth rate.  
  • 99%-plus: The amount the cost of solar panels has fallen since 1978, when RGS Energy sold the first retail solar panel for $100 per watt. Today, a standard solar panel costs around $0.65 per watt.  
  • 3 minutes: How quickly SolarCity (SCTY.DL) recently said it's signing a new solar customer -- every three minutes in the 14 states it operates in. 

An aerial image of Solar Star, which at 579 MW will be the world's largest solar plant when completed. Image: SunPower. 

Solar is already big business
The solar industry has gotten a bad rap after the failure of high-profile companies like Solyndra, but it's a huge business that very successful investors are betting big on. 
  • 579 MW: The size of the largest solar power plant in the world, currently being built by SunPower. When completed, this single project will provide enough power for 400,000 homes.
  • $2.5 billion: The amount Warren Buffett's Berkshire Hathaway subsidiary MidAmerican Energy paid for SunPower's 579 MW Solar Star project. 
  • 377 MW: The size of the Ivanpah concentrated solar system, which NRG Energy (NRG -0.78%), Google, BrightSource Energy, and Bechtel recently completed. It is the largest solar concentrator in the world and will provide enough power for 140,000 homes.
  • 4.8% and 4.59%: The yields on SolarCity's first two securitization deals. Solar power is becoming big business in the financial industry, and in the past six months, SolarCity has completed the industry's first two securitization deals for $54.4 million and $70.2 million, with interest rates of 4.80% and 4.59%, respectively. 
  • $5.7 billion: Solar financing is just getting started, and GTM Research predicts that the residential market will see financing grow from $1.3 billion in 2012 to $5.7 billion by 2016. This is big business, folks. 

Putting the potential power of solar in perspective
Still skeptical of solar energy? Think it'll only be a bit player in our energy future? Take a look at these numbers.

  • 600%: The percentage of the United States' electricity demand you could generate if you filled the Mojave Desert -- which is 25,000 square miles and covers about 0.66% of the United States' land mass -- with SunPower's most efficient production solar panels. Put another way, this one desert could generate more than enough energy to power the world.
  • 59.1%: The amount of Germany's energy that came from renewable energy on a sunny day late last August. Of that amount, 11.2% came from solar, and as GTM Research cheekily pointed out, the grid did not explode.  

Even car companies are now looking at solar as a way to generate power, as shown by this Ford concept car using SunPower cells. Image: SunPower.

Investing in solar isn't as scary as it used to be
In 2012, solar manufacturers took it on the chin as oversupply hit the market and module prices dropped like a rock. But some manufacturers and installers are now separating themselves and provide incredible opportunities for investors.

Investors can get solar exposure through manufacturers like SunPower or First Solar, which also build projects, or through downstream installers like SolarCity. There are also ways to play the owners of these projects, which are collecting cash for 20 years or more from them -- companies like NRG Energy or its new offshoot, NRG Yield, which is one of the first yieldcos, which are companies that own solar projects and pay a dividend with the cash flow. 

Solar is a growing business, and I hope these statistics put both the progress and potential for this industry in perspective. The growth cycle for solar has just begun, and investors who get in early can ride the wave for the next few decades.