Solar PV has become more affordable globally, with module prices declining over 80 percent in seven years, spurred by 44 percent annual average compound deployment growth. Between 2010 and 2016, the global weighted average total installed cost, including all hardware and balance-of-system components, fell by 65 percent. At the same time, the levelised cost of electricity (LCOE) for utility-scale solar PV projects fell by 67 percent, according to a new study released by the International Renewable Energy Agency IRENA.

Although utility-scale solar PV projects regularly make headlines for record-low prices, small-scale rooftop solar PV systems represent an important part of the market and are bringing the benefits of modern electricity services to households that previously had no access to electricity, reducing electricity costs on islands and in other remote locations that are dependent on oil-fired generation, as well as enabling residents and small businesses to generate their own electricity. The costs of electricity from residential rooftop solar PV are falling rapidly. In just over six years, these costs have fallen 45 percent for cities in California and 66 percent in German cities. »This rapid reduction saw the median LCOE of residential solar PV fall below the average effective electricity tariff that applies to these residential customers in six out of the nine cities analyzed in this report. In those six cities, the median LCOE fell from between 75 percent and 104 percent higher than the average electricity tariff (in Munich and Cologne respectively) in Q1 2010, to between 3 percent and 37 percent lower in Q2 2016 (in San Diego and Munich respectively),« says the organization.