FreQuently asked questions

What is a tethered microgird?

A series of loads and energy supply that is connected through automation to use the grid as a variable input, but at no time exports to the grid.

How does the current climate of grid saturation on Kauai affect you?

Grid saturation means there is too much residential solar for the utility to comfortably continue to allow customers to add rooftop solar to their home or businesses.  The utility on Kauai no longer wants to trade energy and has taken steps to limit the amount of solar PV that a customer can connect.   Customers can no longer size their home PV systems to over generate energy to the grid, create credit, and achieve a zero bill.   On Kauai you may install about 30% of your historical load and if you want to install more grid connected solar PV it will need to be curtailed with its own dedicated smart meter. Any solar power running through a curtailment meter is subject to KIUC control at any time. With the price of electricity hovering around $0.30 per kWh and the trade in value of the Q-schedule at $0.10 per kWh, net metering is clearly not the deal it used to be!

What is customer self-supply?

A utility customer is allowed to install Solar PV that does not export electricity or receive compensation.  The utility grid is essentially the ‘back-up generator” for the homeowner.   This customer self-supply approach has been in use for a while, mostly for commercial applications, but now has made its way to residential as a smart home or microgrid.  Now, instead of using the grid for credit, the grid becomes the backup for a smart system that uses automation to limit export and use  storage to catch the over generation to supply 80 to 100% of your energy.  Solar PV can still give you a Zero bill without net-metering from the Utility!

For example, during the day, when most people are not at home and energy is being generated on the homeowner’s roof, the electricity is diverted into a storage system.  Most homes reach a peak power demand between 6 and 10 pm.  The “micro-grid” home releases the stored energy when it’s actually needed.  Customer self-supply with energy storage controlled as a home micro-grid makes the best current use and investment of rooftop solar.  In the case of a utility outage the customer has a bonus of energy independence with backup power.

How much will it cost?  

Cost varies based on your usage, and the chemistry and quality of your battery.  Solar Plus’s holistic energy solutions starts with improving energy efficiency within your home, and then working to minimize your electric bill.   In some cases Solar Plus Kauai will recommend changes in lighting or refrigeration.  Next might be energy savings made possible by smart home automation.  Finally your solar system will be the right  size and cost because all effort has been made to shrink energy budget of your home or building.

Time of Use rates are almost the inevitable next step of the local utility and are currently offered as a pilot program.  Time of Use rates, however,  are also minimized by clever use of the battery when rates are high.    By incorporating best energy practices in your home,  the Solar Plus energy solution will be more affordable, more custom,  and an overall better investment.


Is solar PV still a good investment? 

YES! Solar PV still has a 65% tax credit! (35% State tax credit and 30% Federal tax credit). Don't miss out on these worthwhile tax credits that will not be around for long. –  Learn more.

Do Solar PV panels require maintenance?

The answer is yes, but it depends on your location.

Dust and dirt are the enemies of your solar production efficiency.  In dry areas with lots of dust, the solar PV panels can lose 3 to 10% of their production.  In these areas panel cleaning may be be required as often as twice a year to maintain optimum energy production.  Solar Plus provides panel cleaning and other maintenance not covered in warranty through its subsidiary Boost Solar   (

What technology do you use?  

Wow, good question! For solar panels, Solar Plus Kauai is the largest user of Solar World panels on the island. Learn more about the batteries we use. Learn more about batteries