How rural Mexico was turned on to solar power

It may be 2015, but across the planet one in seven of us lack access to electricity. In rural Mexico, one company is looking to transform the lives of people with a reliable, safe and clean form of energy.

Ilumexico was founded in 2009 and develops lighting and electrification programs for homes, schools, community centres and health clinics. The social enterprise says that three million people in Mexico lack access to electricity in their households.

Their solar home systems have been designed to be clean, bright and affordable.

"Generally families spend 10 percent of their income on alternate sources of energy, so it is that same amount that they now use for paying their installments over 12 months," Louisa Martinez, a field officer for Ilumexico, told CNBC's Sustainable Energy.

A micropayment plan encompassing monthly payments enables customers to purchase the systems in an affordable way.

Ilumexico say that the spend for their clean solar technology is equivalent to the money people would spend on diesel, candles and other sources of light that are polluting and damaging to health.

To date, Ilumexico state that they have installed 3,500 systems and 100 kilowatts of solar capacity. This, they say, has helped to displace 1,720 tonnes of CO2.

Key to the system is the Prometeo, an electric controller which Ilumexico describes as "the brain".

The Prometeo has been designed to regulate the amount of electricity between the system's photovoltaic panel and batteries, and users are able to control the intensity of light with a simple button system.

The impact of Ilumexico's work on Francisco Florentino Santos' life has been significant. "After spending my whole life without electricity, this is going to be a great improvement," he said.

"We have always had to wake up very early to grind our corn manually," he added. "We will now be able to rest longer and have more time."

"We've lived more than 40 or 50 years without electricity," Abram Diaz, another customer, said. "Other places have gotten electricity, but we hadn't," he added.

"But now with this, we are good. We are now able to see, able to work better. This is good. We are great."