Hawaiian Electric Co. has put online graphs that show how much solar and wind power is being generated on Oahu, Maui and Hawaii island throughout the day and how much the renewable sources contribute to total power consumption.
The utility wants consumers to understand the variable nature of solar and wind power and the important role of the so-called "firm" power generated at HECO plants.
"To maintain reliable electric service for all customers, utility engineers must adjust the output of firm sources of generation up or down as the output from variable sources like solar and wind rises and falls throughout the day," HECOsaid in a news release.
The installation of solar photovoltaic systems in Hawaii set another record in 2013, although the once-explosive pace of growth slowed significantly as electric utilities took a cautious approach to allowing PV systems to connect to the grid in areas where high levels of solar power generation are raising concerns about safety and reliability.
Hawaiian Electric Co. and its subsidiaries have issued new specifications for the installation of rooftop solar photovoltaic systems that the utility says will allow more homeowners to put up PV panels in neighborhoods with high levels of solar power generation.
The new technical standards specify the speed at which a PV system needs to be able to disconnect from the circuit in the event of a voltage spike, according to information HECO sent to PV installers Wednesday.
The installation of solar photovoltaic panels across areas served by the Hawaiian Electric Companies rose last year at the slowest rate since 2010, the utility reported Wednesday.
There were 17,609 photovoltaic systems with 129 megawatts of generating capacity installed on Oahu, Hawaii island and Maui County in 2013, up 39 percent from the previous year. That followed annual increases of 136 percent in 2012 and 143 percent in 2011. PV generating capacity in 2010 rose 33 percent across the utility's service area.
Energy collected by homeowners' panels taxed the state's power grid and the local utility has stopped connecting them
For more than four decades, sunny Hawaii has led the way in clean, renewable energy.
Today, 10 percent of all households in the Aloha state have rooftop solar systems to generate electricity, compared with no more than 3 percent in California. But now, Hawaii is facing a problem — the increase of privately installed solar panels has overloaded the power grid.