Enphase Ensemble Technology System Planning Tech Brief

Planning an Ensemble Technology System – North America

Non-backup Configuration - Installing Ensemble without Enpower

The Encharge storage system can be added to an existing system without using an Enpower smart switch, however,

it will not provide backup. When installed in this configuration, Encharge storage system is treated as a distributed

energy resource (DER) equivalent to a PV system and cannot form an intentional island. It may be connected in the

IQ combiner or on a user-provided distribution point in compliance with the NEC. Ensure that the consumption CTs

are installed on the line-side of Encharge storage system interconnection point and that Encharge storage system

circuits are not included in the production CT.

Figure 5: Grid interactive Encharge storage system installation with no backup

Use Cases and Sizing

Load Analysis

The first step in correctly sizing a system is a proper load analysis. If an IQ Envoy with correctly configured

consumption CTs is already installed at a site, you can use data from Enlighten to properly size the system. A site

survey, electric bills, and third-party consumption meters can also provide useful load data for system sizing. Please

also review the Enphase Ensemble Project Survey document at estimator.enphaseenergy.com.

Backup Use Case

A backup system provides power to loads when the grid is down.

It is important to differentiate the terms power and energy. Power is a measure of the instantaneous electricity used

and it is expressed in units of watts (W) or kilowatts (kW). Energy is the accumulated or integrated power used over

time and it is expressed in units of watt-hours (Wh) or kilowatt-hours (kWh). When running in the backup operation,

any power capacity shortages or energy capacity shortages will result in a loss of power to loads and should be

avoided. Therefore, it is important to properly size the system for both power and energy capacities in each

installation.

Sufficiently size the total Encharge storage system power rating to power loads and charge from PV power

generation. You can increase the power rating by adding additional Encharge storage units, which also provide

additional energy, improving the customer user experience.

• Power (kW) capacity from Encharge storage system must exceed the maximum single load and 67% of

total IQ 7 or IQ 6 AC nameplate installed at the site (Table 1).

o 2017 NEC 690.10 -> 710.15 (A) Supply Output. Power supply to premises wiring systems shall be

permitted to have less capacity than the calculated load. The capacity of the stand-alone supply

shall be equal to or greater than the load posed by the largest single utilization equipment

connected to the system. Calculated general lighting loads shall not be considered as a single load.

• Energy storage (kWh) capacity should be sized to supply to the estimated backup loads for a user defined

time period.