The race for the world’s most efficient solar cells got a step closer to 50 percent efficiency as one group reached a new world-record for efficiency. Meanwhile utilities in Arizona and Georgia are raising controversy as they attempt to change the solar equation to benefit them more. That’s even as another study shows the popularity of solar with homeowners is on the rise.

The efficiency of solar cells continues to rise. In fact, Soitec and its partners, Fraunhofer Institute for Solar Energy Systems ISE, CEA-Leti and the Helmholtz Center Berlin recently introduced the world to a new PV cell that reached a conversion efficiency of 44.7 percent. The French company said that the new solar cell is a huge step towards making PV cells that approach 50 percent efficiency levels.

Still there are those who oppose the widespread adoption of solar. Last week, Arizona Public Service (APS), the state’s largest utility, came under fire for a potential strategy proposed by a lobbying group that would have given the utility more control of the state’s regulatory agency, the Arizona Corporation Commission (ACC). While APS said it did not act on the proposal, it appears that the company has engaged in some of the activities recommended in the proposal, drawing the ire of renewable energy organizations statewide. APS has tried to reduce its net-metering requirements several times during the past year, but thus far, it has not succeeded.

Similarly in Georgia, the state’s utility, Georgia Power, is attempting to make the equation on distributed solar, like solar on homes, more favorable for itself. The company has proposed a new fee on solar homeowners that would add roughly $22 a month to electric bills. The company would also raise rates for people without solar by roughly $8 a month. The Georgia Solar Energy Association (GSEA) has spoken out against the proposed tariffs.

Such proposals are being tossed around,  even as interest in solar is increasing. A study recently published by the Center for American Progress (CAP) found that the middle class is leading the way for solar adoption. The new study looked at residential solar in three leading U.S. states, Arizona, California and New Jersey. It found the majority of solar installations are on homes owned by people who make between $40,000 and $90,000 annually.

The study also found that many of these homeowners are going solar through a third-party ownership option like a solar lease or power-purchase agreement. The models being developed in the U.S. are drawing increasing interest from energy companies and even international investors. In fact, just last week, OneRoof Energy announced that it global energy company GDF SUEZ purchased a minority stake in OneRoof. The minority stake will help OneRoof expand into new markets and allow the companies to develop new products for such markets.