Many measures gauge the progress of renewables’ ongoing quest to become a mainstream source of power. Among them is the race to surpass traditional sources for share of total energy production. In this regard, renewables have made great strides. In fact, according to one report, they have recently passed a milestone.

The most recent Monthly Energy Review, published in August by the U.S. Energy Information Administration, reports that total domestic production from renewables in the first five months of 2011 exceeded that of nuclear power and is close to overtaking oil.

Specifically, measuring output in an across-the-board, overall comparison of total energy produced, renewables provided 3.875 quadrillion British thermal units (Btu), which accounts for just over 12 percent of total U.S. energy produced. That is also a 16 percent increase from the first five months of last year.

While this year-over-year growth is significant, the numbers are even more compelling when compared to the growth of other sources of energy. For example, the total production for renewables was 18 percent greater than that of nuclear power, which provided 3.292 quadrillion Btus. Renewables surpassed nuclear for the first time ever in the first quarter of this year. Also, at 79 percent of the energy produced by domestic crude oil, renewables are closing in on that historically dominant source of power.

The growth of renewables was driven by a healthy collective expansion in all of the various sources that make up the industry. For example, solar-generated electricity expanded by 35 percent. Wind-generated energy production grew by 1.5 percent. Hydro-electric power generation saw a 36 percent jump. Geothermal-energy production increased by 4.5 percent, and biomass increased by 16 percent.

The share of energy within the renewable sector that is provided by the various sources is almost the inverse to their growth. For example, one of the fastest growing sectors, solar makes up only 1 percent of total energy produced by all renewables. On the other end of the scale, biomass, which saw much slower growth, accounts for the largest share, 25 percent, of total energy produced by renewables.