Walmart, Costco and Kohl's topped the 2013 Solar Capacity Rankings, which ranks companies by the total installed capacity of their systems and the number of operating installations, as well as showing the geographic diversity of their solar deployment.

Apple, IKEA, Macy’s, Johnson & Johnson, McGraw-Hill, Staples and Campbell’s round out the top 10.

Solar Means Business 2013 shows that overall, the top 25 firms have installed more than 445 MW of solar PV capacity (enough to power 73,400 American homes) across the country, up from about 300 MW last year. While the list is made up of many of the same companies ranked last year, the new rankings show the growing solar portfolios of many of the country’s leading businesses and the continued development of the overall commercial market.

The report says this growth also is occurring in new state markets – the companies analyzed for the report have deployed systems in 30 states and Puerto Rico. Solar has become so ubiquitous that more than one out of every three Americans lives within 20 miles of at least one of these businesses’ solar installations.

Electricity costs represent the single largest operating expense for many businesses. More and more firms are turning to solar, as system prices continue to fall and financing models merge that can reduce up-front costs. In a growing number of markets, companies can either generate or purchase solar energy at or below local retail electricity rates, immediately saving businesses money.

Utility price volatility also presents a challenge to businesses’ long-term budgets, according to the report. Solar allows companies to lock in fixed energy prices for decades. Whether the system is purchased upfront or financed through a Power Purchase Agreement (PPAs) or lease, solar offers long-term price visibility and a valuable hedge against rising and volatile conventional electricity rates. In addition, companies are learning that they can offset tax liability using the federal investment tax credit while powering their facilities as well.

The report concludes that an investment in solar allows American companies to reduce energy costs, allocate resources to their core business operations, and better plan for the future.

In other solar news, Abengoa, an international company that applies technology solutions for sustainability in the energy and environment sectors, was recently selected by the Ministry of Energy of the Chilean Government and Corfo (Corporacion de Fomento de la Produccion) to develop a 110 MW solar plant using tower technology with 17.5 hours of thermal energy storage using molten salts. Located in the Atacama Desert, the region with the highest solar radiation concentrations in the world, the project will be the first solar-thermal plant for direct electricity production in South America.