What is Net-Metering?
How Net Metering works
-
What is net metering?
-
What is the difference between net metering and net billing?
-
Can I apply net metering in the Philippines?
-
What is the approximate cost?
-
What are the technical requirements to be net metering compliant?
-
What are the documentary requirements for net metering?
-
Export limiter, what is its function?
Grid tied installations with a net metering contract with the utility can send their surplus electricity back to the grid. The utility will buy that at a set rate. Solana4U is familiar with the application process. We can do that for you or we can explain it so you can do it yourself.
In layman terms net metering can be explained as a conventional off-grid installation where the battery functionality is taken over by the utility. In the daytime you charge this “utility-battery” to consume its power back during the night when the solar system is not producing.
The obvious advantage is that the utility is never “fully charged”; you can export as much power as you want. This in contrast to battery systems where the solar system shuts off by the charge controller if the batteries are fully charged. Another obvious advantage is the simplicity of the system and lower price because batteries do not need to be purchased. For more on advantages and disadvantages look at “solar systems explained”.
Important to realize that in the Philippines the utility will normally not pay you in cash for the exported power. Any credit is forwarded to the next month. This is why it is important to contract a transparent solar company who can quote the exact right solar capacity for your individual needs. An honest contractor will give you two options. The size of a system which can achieve “zero billing” and the price of a system which achieves fastest return of your invested money. The last is always smaller and cheaper. It is common sense not to be drawn to a zero-billing solution when that solution has less financial benefit in terms of ROI.
In the Philippines the maximum allowed solar system to apply for net metering is 100kW. In normal residential and small commercial solutions this is more than enough. While residential applications are still a valid option for solar, the return of investment is slightly longer (4-5 years) as compared to a “day time 7 days a week business” which has a 3-4 year return.
For residentials with a 5,000 – 6,000 Peso bill a 5kW system is often sufficient to achieve the fastest ROI.
The term “net metering” is widely used in the Philippines; but actually, that is a bit confusing. It gives the false impression that the “net” meter reading backwards is compensated one-on-one back to the customer. This is not the case. The term “net billing” would be more appropriate and accurate. This is because in the Philippines only the “generation charge” is compensated back to the customer. This immediately explains why net metering has a faster ROI in those installations with a relatively higher daytime consumption (operating in day-time hours, 7 days a week). This in contract to those residential applications where the return of investment depends on the exported power to the grid. In short: solar is always more beneficial if the generated power is directly consumed. Selling back to the utility and (worse) charging batteries is to be regarded as a secondary option.
By law, (renewable Energy Act of 2008), the utility has to accept the net metering; they cannot refuse. Still, for some utilities in the province, there is not always familiarity with the requirements and application and that causes sometimes delay. Established solar companies, specialized with the net metering process can apply on your behalf.
The cost for the net metering is around 10,000 Peso for the technical requirements and also 10,000 for the documentary requirements. Aside from that there is the application cost at the utility which varies anything between 7,000 and 32,000 Peso. Best is to inquiry at your installer for the up-to-date pricing!
The technical requirements vary from utility to utility also because the LGU engineering office is involved in the application process.
In general, the technical requirements as of writing this information:
-
Approved inverter type brand/model.
-
Inverter to have islanding functionality (this means it will automatically shut off/disconnects when the utility suffers power outage.
-
Approved “start-up time” not less than 600 seconds.
-
Approved “reconnect time” not less 120 seconds.
-
REC meter, production meter accessible by utility to monitor the produced solar power.
-
Disconnect switch, accessible by utility to disable the solar system to ensure the safety of linesmen working on the distribution system.
-
The installation has to be compliant with the Philippine Electrical Code.
-
The installation has to be done under the supervision of and Electric Engineer.
In general, the most important documentary requirements as of writing this information:
-
Latest Electrical bill (in name of applicant)
-
ID of applicant
-
Letter of intent.
-
Occupancy permit (in name of applicant)
-
Approved electrical plan, in name of applicant, signed by PEE (PEE=Professional Electrical engineer)
-
Sometimes a inspection report of a civil engineer to attest the load of the panels can be carried by the roof.
-
CFEI (Certificate Final Electric Inspection).
In the Philippines contractors install “export limiters” in grid tied systems to avoid export to the grid for the duration that the net metering application is in process. It does what is says…. It is limiting (eliminating) the export to the grid of a grid tied installation. This is important. When the installation is not yet approved to export all the exported power will be CHARGED AGAINST YOU. (even if the utility meter is turning reverse, the digits still add up!) Not all inverters are suitable to be fitted with this export limiter.
This is the main reason that only a few selected grid tied inverters are popular and suitable in the Philippines. AFTER the net metering is approved by the utility the export limiter will be dismantled and its functionality in the inverter disabled. Of course, at that stage all grid tied inverters are suitable because then the export limiting function is irrelevant. We like to note that the export limiter is (sort of) exclusively used in the Philippines only, and then for a short period of time only (duration of net metering application). The export limiter and its CT sensor are vulnerable and not designed to be deployed for prolonged period at the service entrance of your house. It is designed for temporary use. We do not recommend to rely on the export limiting function for a prolonged time.
Keywords: net metering, net metering application, net billing, export limiter.
