Every hybrid inverter gets a score from 0 to 100% built from five factors, which maps onto the 5-point rating shown on the site (a 0% score would be 1.5 stars; a perfect score, 5). Each factor is scored against fixed reference points, not against the other products in the list, so adding a new model never moves another model’s rating. 120 V and 120/240 V split-phase inverters are ranked separately.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per kW of continuous output | 30% |
| Solar input | panel watts it takes, PV voltage and trackers | 20% |
| Efficiency | peak efficiency and idle draw | 20% |
| Features | UL 1741, app, parallel, sell-back, generator and battery links | 15% |
| Warranty | warranty length | 15% |
Where the numbers come from
Output, solar input limits, efficiency, idle draw, features and warranty come from the maker’s datasheet, manual or warranty page. UL 1741 counts only where the maker states the unit is listed or certified, not merely “compliant”. Efficiency and idle draw are the maker’s own figures; independent measurements are listed on product pages where a reviewer has published them.
The factors
Value is the price divided by the continuous output: dollars per kW.
| Output | Scores 0 | Full marks |
|---|---|---|
| 120 V | $400 per kW | $100 per kW |
| 120/240 V split-phase | $700 per kW | $200 per kW |
Split-phase inverters get their own scale because making 240 V from one unit, along with the grid-tie hardware most of them carry, costs more per kW.
Solar input measures how much of a solar array the inverter can use:
| Part | Share of the factor | Scores 0 | Full marks |
|---|---|---|---|
| Maximum PV watts per watt of continuous output | 60% | 0.8 | 2.0 |
| Maximum PV voltage (Voc) | 25% | 145 V | 500 V |
| Independent MPPT trackers | 15% | 1 | 3 |
More PV watts than output lets the inverter charge the battery while running loads, and keeps charging on cloudy days. A higher PV voltage means longer series strings and thinner wire. More trackers let you point panels in different directions or mix panel types.
Efficiency is half the maker’s peak inverter efficiency (90% scores zero, 97.5% full marks) and half its idle draw, the power the inverter uses when switched on with nothing plugged in:
| Output | Scores 0 | Full marks |
|---|---|---|
| 120 V | 80 W idle | 20 W idle |
| 120/240 V split-phase | 150 W idle | 40 W idle |
Only a battery-to-AC efficiency counts. Some makers publish just a single “max” efficiency, usually measured from solar to AC, which runs 3 to 5 points higher; that figure is listed on the product page but not scored, and the efficiency half of the factor gets the neutral score.
Idle draw runs around the clock, so in an off-grid system it often costs more energy than conversion losses do: 60 W of idle draw is 1.4 kWh a day.
Features adds up the things that make an inverter easier to permit, monitor and grow:
| Feature | Share of the factor |
|---|---|
| Listed to UL 1741 (needed for most permitted grid-tied installs) | 30% |
| Wi-Fi app monitoring in the box (half credit for an add-on) | 20% |
| Parallel stacking of more than one unit | 15% |
| Grid sell-back (export) | 15% |
| A dedicated generator input | 10% |
| Closed-loop communication with a lithium battery’s BMS | 10% |
A feature the maker doesn’t state either way gets half credit.
Warranty: 1 year scores zero and 10 years full marks.
What isn’t scored
Surge rating, charge current, MPPT voltage range, transfer time, CEC efficiency, enclosure rating, size and weight are listed but not scored. Independent tests are listed where they exist, but there are too few to score.
Missing data
If a figure isn’t published, that part of the factor gets the neutral middle score (50) and the product page marks it as estimated.
Ties and discontinued models
Products are ranked by score within each output type. Discontinued models stay listed but rank below every current model and can be hidden with the “Hide discontinued” filter.