What is net metering in Puerto Rico?

Net metering is a mechanism regulated by the Puerto Rico Energy Bureau (PREB) that allows solar system owners to send the energy they do not consume back to the LUMA grid. A bidirectional meter records both the energy you draw from the grid and the energy you export. At the end of the month, you only pay the net difference: if you exported more than you consumed, you receive a credit on your next bill.

How much does LUMA pay me for the energy I export with net metering?

Under the net metering program in Puerto Rico, LUMA credits the exported energy at a rate set by PREB, which is typically lower than the rate you pay for consumption. This means it is in your interest to consume as much of your own solar energy as possible in real time and export only the surplus. The credit appears as a discount on your monthly LUMA bill.

What happens to my net metering credits at the end of the year?

Net metering credits in Puerto Rico accumulate month to month. If in a given month you export more than you consume, the credit carries over to the next month. At the end of the annual settlement period, any accumulated credits that have not been used are generally settled according to current PREB rules. That is why it is important to size your system correctly so that annual production is close to your annual consumption.

Do I need a special meter for net metering in Puerto Rico?

Yes. To participate in the net metering program you need a bidirectional meter that records the flow of energy in both directions: the energy you draw from the grid and the energy you export from your solar system. LUMA installs this meter as part of the interconnection process. The cost of the meter and its installation are included in the interconnection process. At Kilowatt PR we manage the entire interconnection process with LUMA so you do not have to deal with paperwork.

How Net Metering Works in Puerto Rico

What Is Net Metering?

Net metering is a policy regulated by the Puerto Rico Energy Bureau (PREB) that allows solar system owners to exchange energy with the electrical grid. In simple terms: when your panels produce more energy than you use, the surplus goes to the grid and you receive a credit. When you need more energy than you produce (for example, at night), you draw it from the grid.

At the end of each billing period, you only pay the net difference between what you consumed from the grid and what you exported. Hence the name: net metering.

How the Bidirectional Meter Works

The heart of net metering is the bidirectional meter. Unlike the traditional meter that only measures the energy you consume, the bidirectional meter records the flow of energy in both directions:

Energy Flow with Net Metering

Day

Your panels produce more than you consume

The surplus flows to the LUMA grid. The meter runs "backward," accumulating credit in your favor.

Night

No solar production, you consume from the grid

The meter runs "forward" normally, but first uses the credits accumulated during the day.

Bill

You only pay the net difference

If you exported 400 kWh and consumed 600 kWh from the grid, you only pay for 200 net kWh.

A Typical Day with Net Metering in Puerto Rico

To better understand how it works in practice, let's look at a typical day for a home with solar panels and net metering in Puerto Rico:

6:00 AM – 8:00 AM: The panels start producing but do not yet cover all the morning consumption (water heater, stove, lights). You partially consume from the grid.
8:00 AM – 4:00 PM: Peak solar production hours. The panels produce significantly more than you consume (the house is empty or has low consumption). The surplus goes to the grid and you accumulate credit.
4:00 PM – 6:00 PM: Production drops while consumption rises (the family comes home, the A/C turns on). You start using accumulated credit.
6:00 PM – 6:00 AM: No solar production. You consume from the grid, but the day's credits reduce your net consumption.

Monthly Credits on Your LUMA Bill

Net metering credits appear on your LUMA bill as a direct discount. There are several possible scenarios each month:

Monthly Billing Scenarios

You consumed more than you exported

You pay the net difference (significantly reduced)

Consumption: 800 kWh | Export: 500 kWh | You pay: 300 kWh

You exported more than you consumed

You receive credit that carries over to the next month

Consumption: 400 kWh | Export: 600 kWh | Credit: 200 kWh

Balanced production and consumption

LUMA bill close to $0 (only minimum fixed charges)

Consumption: 600 kWh | Export: 580 kWh | You pay: 20 kWh

It is important to note that even with net metering, your LUMA bill never reaches exactly $0 because there are minimum fixed charges that apply regardless of your net consumption. However, it is possible to reduce your monthly bill from $300–$400 to $20–$50. This magnitude of savings is possible because Puerto Rico has one of the highest residential electricity rates in the entire United States according to data published by the U.S. Energy Information Administration (EIA), which increases the value of each kWh you replace with your solar production.

Annual Credit Settlement

The credits you accumulate carry over month to month. This is beneficial because solar production varies depending on the time of year: in summer you produce more and in the rainy months a little less. The credits from high-production months offset the lower-production months.

At the end of the annual settlement period, the accumulated credits are handled according to current PREB rules. That is why sizing your system correctly is essential: we want your annual production to be as close as possible to your annual consumption to maximize the benefit and minimize the credits lost at settlement.

The Role of PREB and LUMA in Net Metering

PREB (Puerto Rico Energy Bureau)

PREB is the regulator that establishes the rules of net metering in Puerto Rico. It defines the credit rates, the technical requirements to participate, the system capacity limits, and the rights and obligations of both the customer and LUMA. PREB also handles complaints if disputes arise with LUMA over net metering credits.

LUMA Energy

LUMA is the entity that operates the grid and runs the net metering program day to day. Its responsibilities include:

Processing the interconnection request
Installing the bidirectional meter
Conducting the interconnection inspection
Calculating and applying the monthly credits on your bill
Handling the annual settlement

Interconnection Requirements for Net Metering

To participate in the net metering program in Puerto Rico, your solar system must meet LUMA's interconnection requirements:

Authorized installer: The system must be installed by an installer with a valid license in Puerto Rico
Electrical inspection: The system must pass the electrical inspection by the licensed electrical contractor
Interconnection request: The formal request is submitted to LUMA with the system plans
LUMA inspection: LUMA inspects the system before authorizing interconnection
Meter installation: LUMA installs the bidirectional meter
Permission to operate (PTO): LUMA issues the final permit so your system can export to the grid

This process can take between 4 and 12 weeks depending on the workload of LUMA Energy and the complexity of the system. At Kilowatt PR we manage this entire process for you: from the initial request until your system is producing and exporting to the grid.

How to Maximize Your Benefits with Net Metering

To get the most benefit from net metering in Puerto Rico, follow these recommendations:

Size your system correctly: An oversized system generates credits you may lose at the annual settlement. An undersized system does not maximize your savings. The ideal point is for your annual production to match your annual consumption.
Shift consumption to the day: Schedule large appliances (washer, dryer, water heater) to run during sunlight hours when your panels produce surplus.
Monitor your production: Use your inverter's monitoring app to verify that your system is producing as expected. An unexpected drop may indicate dirt or a technical problem.
Consider a battery: With a battery you can store surplus for nighttime use instead of sending it to the grid, maximizing self-consumption and reducing dependence on net metering credits.

Net Metering vs. Battery: Are They Complementary?

Net metering and a battery are not mutually exclusive: they are complementary. Net metering lets you "use the grid as a virtual battery" during the day, while a physical battery protects you during outages when the grid is not available. The ideal combination for many homes in Puerto Rico is to have both: net metering to maximize monthly savings and a battery for backup during LUMA's frequent outages.

Conclusion: Net Metering Is Key to Your Return on Investment

Net metering is what turns your solar investment from a self-consumption system limited to daytime hours into a 24-hour savings solution. Without net metering, the energy you produce and do not use during the day is wasted. With net metering, every kilowatt-hour you produce has value, whether you consume it directly or send it to the grid as a credit.

At Kilowatt PR, with technicians and crews with over a decade of experience in Puerto Rico, we size your system to maximize the benefit of net metering and manage the entire interconnection process with LUMA so you only have to worry about enjoying the savings.