Net Metering in Panama: How Solar Self-Consumption Is Billed Today
For solar self-consumption to operate legally, safely, and with financial clarity, it is essential to understand how the system connects to the grid, how energy is measured, and how that energy is reflected on the electricity bill.
In Panama, the regulatory framework for self-consumption using new, renewable, and clean energy sources was approved by ASEP through Resolution AN No.10206-Elec of July 11, 2016, and later modified by Resolution AN No.10299-Elec of August 10, 2016.
Today, the applicable procedure is based on a scheme known as net metering. Recent regulatory discussions have introduced another concept: net billing. Although both models relate to self-consumption, they do not produce the same economic outcome for the user.
1. The Current Net Metering Scheme: The Bidirectional Meter as the Key Component
ASEP’s procedure establishes that a self-consuming customer must connect to the grid through a bidirectional meter. In practical terms, this meter records two flows:
the energy the customer takes from the grid when consumption exceeds solar generation;
the energy the customer sends to the grid when the solar system produces more than what is being consumed at that moment.
The distribution company must install this bidirectional meter at its own cost and determine, in each billing period, the net balance between the energy received from the grid and the energy delivered by the customer. Under the self-consumption scheme, the customer may inject surplus energy into the distribution grid whenever the solar plant produces more than needed at that moment.
2. How It Appears on the Electricity Bill?
The procedure includes two main scenarios for monthly billing.
Scenario 1: Net Consumption (when you use more grid energy than you produce)
This occurs when, at the end of the month, your home consumed more electricity from the grid than your panels delivered to it. In this case:
The bill charges only the difference (the energy you actually needed from the grid).
It also includes the fixed charge and other standard tariff components.
Scenario 2: Net Injection (when you produce more energy than you consume)
This occurs when your panels delivered more energy to the grid than you used from it. In this case:
The surplus energy becomes credits in kWh.
These credits are saved and applied to future bills according to the self-consumption rules.
In summary: Your surplus becomes energy credits you can use later.
3. Energy Credits Are Not Unlimited
A point often overlooked in public discussions is that net metering in Panama does not allow customers to inject unlimited energy without economic or technical limits.
ASEP establishes that customers may store unused solar energy as kWh credits, but only up to a maximum of 25% of their annual or semiannual consumption. This limit is calculated using the customer’s consumption history and is documented in the Interconnection Agreement signed with the distribution company.
Practically speaking, this means that a solar system should not be designed simply to “fill the roof with panels.” A good design must consider the consumption profile, usage hours, applicable tariff, and the real ability to use the generated energy.
4. Why the Consumption Profile Matters More Than It Seems
Two customers may have similarly sized solar systems yet obtain very different economic results.
A home where most consumption occurs at night may rely more on the balance between electrical consumption and solar generation, because daytime production is not always consumed directly. In contrast, a home with daytime consumption—due to remote work, air conditioning, or other active equipment—can take better advantage of real-time solar generation.
In commercial settings, the picture changes. Many businesses operate precisely during the day, when solar systems produce the most. Offices, supermarkets, workshops, restaurants, clinics, logistics centers, or businesses with refrigeration often have a high overlap between solar generation and electrical consumption. In these cases, direct self-consumption is a major component of savings.
5. What Would Change Under a Net Billing Scheme?
Recent documents associated with ASEP’s public consultation processes have discussed the possibility of shifting from net metering to a net billing scheme for self-consumers.
The core difference is this:
Under net metering, consumed energy and injected energy are balanced in kWh to determine a final net value.
Under net billing, the energy the customer consumes from the grid and the energy delivered to the grid are valued separately, usually at different prices.
With net billing, the customer would continue paying for grid energy according to the regulated tariff. However, surplus energy delivered to the grid could be recognized at a different price—typically associated with the cost of the energy used for injection (solar energy), not necessarily the same price the customer pays for purchased energy.
This can significantly change the financial analysis of a solar project. If the recognized price for injected energy is lower than the price of purchased energy, the incentive shifts toward consuming as much solar energy as possible at the moment it is produced.
6. Potential Impact on Homes, Businesses, and Communities
For households, the main effect would be on the payback period. Homes with low daytime consumption that rely heavily on how surplus energy is discounted or applied could see reduced economic benefits if a less favorable net billing scheme replaces current net metering.
For businesses, the impact would depend on the overlap between solar production and operational consumption. A business with high daytime usage may still benefit greatly from self-consumption. In contrast, businesses with nighttime loads, weekend closures, or consumption concentrated outside solar hours may depend more on how surplus energy is valued—and therefore be more affected by a change in the injection rules.
For communities, buildings, and collective projects, the change could be even more sensitive. These models require clear rules for measurement, benefit distribution, and technical responsibility.
7. Regulatory Transitions Must Protect Confidence
Reviewing self-consumption rules is not inherently negative. Electrical grids require price signals, operational safety, technical limits, and sustainable mechanisms for all users. However, any transition must protect the confidence of those who invested under the current framework.
A shift from net metering to net billing should clarify at least:
what will happen to customers already under the current scheme;
whether transition periods will exist;
the price of injected energy;
how that valuation will appear on the bill;
what will happen to accumulated credits.
Regulatory stability is essential because solar energy is a long-term investment. When rules are clear, users can make confident decisions and the market can grow more orderly.
Conclusion
The debate between net metering and net billing is not just technical. It affects how families calculate savings, how businesses recover their investment, and how Panamanian communities participate in the energy transition.
Energy education is not a complement to self-consumption. It is the foundation that allows homes, businesses, and communities to make responsible, profitable, and sustainable solar decisions.
Are you evaluating a solar system for your home, business, or community?
Book a consultation with El Roblillo and we will review your case with technical criteria, clarity, and responsible guidance.
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