Frequently Asked Questions


How does a photovoltaic system work? 
A photovoltaic system converts sunlight directly to electricity. An array consisting of solar modules (panels) captures sunlight and converts it to Direct Current (DC) electricity. In a grid-tied system, this DC electricity is sent to an inverter, which converts it to Alternating Current (AC). This AC electricity is then fed into your building electrical system, offsetting some or all of the AC electricity you are purchasing from the utility company.

In a standalone system, there is no utility connection. The DC electricity from the modules flows to a charge controller, and then to storage batteries. The batteries typically supply DC electricity to the site equipment. In some cases, the DC is then converted to AC if required.

What happens when utility power fails? 
A grid-tied system will immediately shut itself off. This is necessary to protect the utility company grid and its workers from your power back feeding onto their system.

What is Net Metering?
A Net Energy Metering (NEM) agreement allows a business or homeowner with a grid-tied photovoltaic or wind system to export excess generated electricity to the utility. This electricity earns credits than can be applied against utility charges within a 12 month period.

Will HECO pay me for the electricity I export to their system?
A NEM only provides retail value credits for exported electricity. However, HECO does offer a Feed In Tariff (FIT) program which allows a business to sell generated electricity at a wholesale rate. 

Is a photovoltaic system a good investment for my business? 
In most cases, yes! The combination of tax credits, reduced utility bills, decoupling from steadily increasing energy costs, property value enhancement, and rapid payback make commercial photovoltaic systems a smart business decision.

Is a photovoltaic system a good investment for my home?
Residential photovoltaic systems offer homeowners many of the same benefits as their commercial counterparts.  However, as depreciation typically does not apply to residential systems, their payback period is longer. 

Should my business wait? Won’t photovoltaic systems be much more efficient and less expensive in the future?
There are several concerns about waiting to install a system. First is HECO circuit capacity. Approximately 15% of all Oahu circuits are at their renewable energy penetration limits. With the number of installations increasing by 300% this year, more circuits will reach their limits and be closed.

Photovoltaic efficiencies increase incrementally, over long time periods. System performance has increased an average of 2% a year over the last 17 years. Contrast this with microprocessor clock speeds, which averaged over 50% improvement per year over the same period.

Finally, module prices have dropped so far in the last 18 months that many manufacturers are barely profitable or have left the business. In addition, overall global demand is weak. As this market selection process continues, prices among the remaining manufacturers will stabilize. 

What is the best photovoltaic module?
There is no “best” module for all applications. Performance, pricing, and manufacturer support must be considered in the context of your site conditions, budget, and expectations. Boss Enertech is vendor-neutral; we do not represent any specific module manufacturer. As such, we can objectively analyze and offer module options and explain the strengths of each, allowing you to make an informed choice.


These are some of the more common questions we receive. For more information, contact us at 488.1411.