Many people are confused by solar photovoltaics, commonly referred to as “PV.” Some of the most commonly asked questions are: “How do the panels make electricity?” “How long do they last?” “What are micro-inverters?” “How do I know how much solar energy is being produced?” And, “Should I start with solar hot water?”

Here are some answers to these questions.


Solar PV panels consist of modules, which are groups of cells. These cells contain semiconductors. When sunlight hits these cells, it causes the electrons in the semiconductors to become excited. This movement of electrons creates direct current (DC) electricity. This DC electricity needs to be converted into alternating current (AC) electricity for our households to run. The panels do not last forever, but most panels are warranted to produce 90 percent of their original rating after 10 years and 80 percent after 20-25 years, depending on the manufacturer.

Electrical current is changed from DC to AC with an inverter. Battery chargers also can use inverters to convert household AC to DC. Newer technology, such as micro-inverters are rapidly taking the lead in most residential PV systems. An individual inverter is connected to each panel and usually mounted directly under the panel. Energy monitoring units communicate with your individual micro-inverters to send notifications in the event of a problem or malfunction. They constantly monitor both the production of the panel and the condition of the power in your home. If any unsafe conditions are detected, they will immediately cut the power connection between the individual panel and your home power supply. You have free access to monitoring your system from your computer anywhere in the world.

It is not always efficient or cost-effective to heat water with electricity, especially with the electric rates that we have here in Hawaii. Converting the sun’s energy directly into hot water is almost always the first and best solution. Additional incentives from HECO reinforce both the concept and the pricing advantage. It is the easiest, cheapest way to make a significant portion of your HECO bill go away.


EnergyPro Hawaii installs many different solar products, including PV systems, hot water systems and attic fans. Call EnergyPro Hawaii today at 596-2890 for more information or a free energy consultation — you have nothing to lose! You also may visit the website at

CONTACT: 596.2890


Image 1 of 2