SYSTEM SIZING – SOLAR (NEVADA)

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When it comes time to properly sizing a solar PV system, the installation contractor will utilize NV Energy’s online application software or will determine the size based upon historical energy usage at the Premise. Premise: All of the real property and apparatus of a residential or non-residential customer employed in a single integrated activity operating under one name in one or more buildings and /or locations on an integral parcel of land where:

  (a) such buildings and/or locations are situated on a single unit of property; or

  (b) such buildings and/or locations are situated on two or more units of property which are immediately adjoining or adjacent, and are not divided by intervening public highways, streets, alleys, railways or waterways.

 

***Systems larger than 25 kW: Solar PV systems sized larger than 25 kW qualify for net metering billing under schedule NMR-B.***

 

- Consumption History The highest energy usage that occurred in 12 consecutive months out of the last 24 months will be used to determine the maximum size of the new solar PV system. If the host customer has not consumed energy at a proposed residential installation location for a 12 consecutive-month period during the two prior years, then the solar system may be sized by using less the livable square footage method or an engineering calculation.

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- The system size can be less than the amount estimated to be used at the premise, but it cannot be sized to create more energy than is estimated to be consumed in a year based on the customer’s annual requirements for electricity. The size of a net metered solar PV system is measured in kilowatts (kW) in alternating current (AC). The CEC AC wattage of a system is the California Energy Commission (CEC) rating of each panel multiplied by the number of panels, then multiplied by the CEC efficiency rating of the inverter(s). The adjustment factor is inherently included in the NV Energy application software.

 

- Energy Audit Report If the customer does not have 12 consecutive months of billing history during the two prior years, or a change in loads or usage behavior is not sufficiently captured in the billing history data, then an energy audit report may be used to quantify the annual amount of energy the customer’s household uses. The energy auditor must have an active license issued by the Nevada Real Estate Division, and all aspects of the energy audit report must follow the standards set forth by the legislative statute NRS 645D.300.

 

***A Net Metering System must be sized to meet no greater than one hundred percent of a customer’s annual electricity needs per its definition in NRS 704.771. ***

- Therefore, a limited energy assessment as described in the NRS 645D regulations will not be accepted in a Net Metering application because it does not account for the entirety of the customer’s loads.

 

The estimated production (kWh) of the proposed system may not exceed the amount of energy usage (kWh) determined by the energy audit report. In the application review process, the energy auditor’s 14 license number will be verified by the Nevada Real Estate Division license lookup. The energy audit report will be reviewed to ensure it maintains the standards set by NRD 645D.300. The computer software that is used in making the energy audit report must be approved by the United States Department of Energy and will be verified during application review. The list of software curated by the Department of Energy can be found here: Approved Software Calculating Energy-Efficient Home Credit. Engineering Calculation

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If energy has not been consumed at a proposed location for a 12 consecutive-month period during the two prior years, or if the customer has a change of circumstances that would make the historical usage calculation incorrect, then a Nevada licensed electrical engineer’s estimated energy usage may be used for systems as an alternative method for estimating usage. Some of the factors that may contribute to a change of energy consumption include:

     • Customers that add on additional square footage to a dwelling that already has a solar installation.

     • Customers that add electric vehicles.

     • Premises that do not have 12 consecutive months of billing history prior to submission of the application.

     • Other significant load changes. The estimated production of the proposed system (kWh) may not exceed the engineer’s calculation. The engineer’s name and license number is verified during the application review process and shall be in the roster maintained by Nevada board of Engineers and Land Surveyors. Electrical load calculations are only valid if wet-stamped and signed by a Nevada Licensed Electrical Professional Engineer. Livable Square Footage The system may be sized based on the interior living area of the residence.

 

**In northern Nevada the solar system may be up to 2 watts (CEC-AC) per square foot of interior living space; in southern Nevada the solar system may be up to 2.8 watts (CEC-AC) per square foot of interior living space.**

 

If 12 months of energy usage history exists, then the watts per square foot of interior living space method may not be used.

System Additions Host customers may interconnect additional capacity at a premise with existing renewable generation capacity. System addition applications are subject to special terms that require review and approval by NV Energy.

The list below addresses some of the considerations for system additions.

     • All renewable generation capacity on a premise that has received or will receive interconnection cannot exceed 1 megawatt (CEC-AC). Systems over 1 megawatt (but not to exceed 20MW) must adhere to the Rule 15 interconnection process. This limitation applies separately for renewable generation systems of other types (i.e. wind and hydro generation).

     • Non-incentive expansion systems on an originally incentivized system will be interconnected so that they do not pass through the existing Portfolio Energy Credits (PEC) meter. The system 15 owner is entitled to keep the PEC credits on a non-incentivized solar system. PECs for any previously installed incentivized capacity that is not separately metered are assigned by the system owner to NV Energy. 

     • In the case of installation of additional capacity on a system receiving production-based incentives (PBIs) the approved expansion capacity does not require a REC meter.