Between 2010 and 2015 solar energy generation increased by over 1,700 percent and renewable electricity accounted for almost 22 percent of all of the state's electricity generation in 2015. From 2014 to 2015, renewable energy generations increased by over eight percent overall with solar power rising by over 40 percent. But because of the drought, hydroelectric energy generation decreased over six percent.

Importantly, the report also shows that with a push towards renewable energy, job and economic growth aren't hampered. In fact, it's quite the opposite. Since California's climate law was passed in 2006, the state's GDP has increased by nearly $5,000 per person -- which is double the increases the US achieved as a whole. Job growth in California was also stronger than the rest of the country by about 27 percent. These achievements were accomplished all while reducing per capita emissions by 12 percent and carbon-intensity by 4.5 percent.

However, while the report shows that the state is doing very well in some areas, it also notes that reductions in greenhouse gases have stalled, falling just 0.34 percent between 2014 and 2015. And those numbers have been leveling out for the last few years. The report attributes the lack of progress in this particular area to cheaper gas prices and increased commute times -- which rose nearly three percent -- as residents are forced to move further away from their jobs due to the rising housing costs in urban areas. "Transportation sector emissions vastly outweigh other carbon-producing areas of California's economy, and the recent spike should alert policy-makers that despite our best efforts, more must be done," Adam Fowler, an economist at the research firm that put the report together, said in a statement.

However, while there's still some work to be done, the progress the state has made shows that its efforts are largely working and should be seen as a standard for other states and the country as a whole. "The data in this year's Index shows that developing cleaner transportation options presents both a great challenge and a great opportunity for the state moving forward," said Noel Perry, the founder of the nonprofit group Next 10, which released the report. "Finding a way to reduce emissions by 5 percent each year in the coming decade will require innovation. Fortunately, that's something California has proven it knows how to do."