Philippine Net Metering FAQs

Philippine Net Metering FAQs

This blog is taken from the "NET-METERING REFERENCE GUIDE" guide book release by Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH

Part 1 of the reference guide is titled "How net-metering works: Understanding the basics of policy, regulation and standards", this blog will try to present Part 1 of the guide as Philippine Net Metering FAQs.

Here's the complete Part 1.

How net-metering works: Understanding the basics of policy, regulation and standards

Author: Atty. Ranulfo Ocampo, President PEPOA, Chairman NREB Sub-Committee on Net-Metering

Q1. What is net-metering?

A1. Net-metering allows customers of Distribution Utilities (DUs) to install an on-site Renewable Energy (RE) facility not exceeding 100 kilowatts (kW) in capacity so they can generate electricity for their own use. Any electricity generated that is not consumed by the customer is automatically exported to the DU’s distribution system. The DU then gives a peso credit for the excess electricity received equivalent to the DU’s blended generation cost, excluding other generation adjustments, and deducts the credits earned to the customer’s electric bill.

Q2. Is net-metering already available in the Philippines?

A2. On 27 May 2013, the Energy Regulatory Commission adopted ERC Resolution 09, Series of 2013 approving the Rules Enabling the Net-Metering Program for Renewable Energy. This resolution was published on 10 July 2013 in newspapers of general circulation in the country and took effect 15 days thereafter. Thus, the Net-Metering Rules took effect in the Philippines on July 24, 2013. The Net-Metering Program is available only to On-Grid distribution systems (or DUs connected to the transmission grid).

Q3. What is the legal basis of ERC in approving a net-metering program for renewable energy in the Philippines?

A3. Section 10 of the Renewable Energy Act of 2008 (Republic Act No. 9513) provides that subject to technical considerations and without discrimination and upon request by distribution end-users, DUs shall enter into net-metering agreement with qualified end-users who will be installing the RE system. The ERC, in consultation with the NREB and the electric power industry participants, shall establish net-metering interconnection standards and pricing methodology and other commercial arrangements necessary to ensure success of the net-metering for renewable energy.

Q4. Why is there a capacity limit of 100 kW placed on RE systems under the net-metering program?

A4. This is because net-metering, as defined under Section 4 (gg) of the RE Law, refers only to a system appropriate for Distributed Generation (DG). DG, as defined under Section 4 (j) of the RE Law, as small generation entities supplying directly to the distribution grid, any one of which shall not exceed one hundred kilowatts (100 kW) in capacity.

Q5. What types of power generating facilities are eligible for net-metering?

A5. RE facilities such as solar, wind, biomass or biogas energy systems, or such other RE Systems not exceeding 100 kW in power generating capacity, capable of being installed within the customer’s premises, are eligible to participate in the net-metering program.

Q6. What benefit will I get if go into net-metering?

A6. By generating electricity for own use, you reduce the amount of electricity you buy from your local DU. The rate of savings (or avoided cost) realized on electricity generated for own use is equivalent to the DU’s retail rate consisting of charges for generation, transmission, system loss, distribution, subsidies, taxes and other charges. You also earn peso credits on any excess electricity exported to the DU equivalent to the DU’s blended generation cost, excluding other generation adjustments. The peso credits earned is then used to reduce

your electric bill/s.

Q7. How will my DU meter my import and export energy?

A7. The DU may opt to install two uni-directional meters – one to meter energy you buy from your local DU, and the other to meter the energy you export to the DU.

The DU may at its option install a single bi-directional meter that can meter both import and export energy if it finds it to be a more economical. The DU may also install a third meter in proximity to your RE facility to meter its total RE generation. The total RE generation shall earn for the host DU RE Certificates which the DU can use to comply with its Renewable Portfolio Standards (RPS) obligations.

Q8. Who are qualified to participate in the net-metering program?

A8. DU customers who are in good credit standing in the payment of their electric bills to their DU are qualified to participate in the Net-Metering Program for Renewable Energy. These customers are referred to in the Rules as “Qualified End-Users” or QE.

Q9. If I am a contestable customer getting my power supply from a competitive Retail Electricity Supplier (RES), am I qualified to participate in the net-metering program?

A9. No. Only distribution end-users (or captive customers) or contestable customers who opted to remain with their DU are qualified to participate in the net-metering program. This is because the excess electricity received by the DU from the QE can only be distributed to the DU’s other customers, and the credit to be given for the excess electricity received by the DU is equivalent to the DU’s blended generation costs. Contestable customers getting their power supply from an RES are thus not eligible to join the Net-Metering program.

Q10. If I am a customer directly-connected to the transmission grid, am I qualified to participate in the net-metering program?

A10. No. Customers directly-connected to the transmission grid are not DU customers but are transmission

load customers of the National Grid Corporation of the Philippines (NGCP).

Q11. How do I determine the DU’s blended generation cost for a particular month?

A11. DUs are required to publish in their websites their monthly generation cost. You only need to access your DU’s websites to get the blended generation cost of your DU for a particular month so that you will know how much credit you are entitled to on any excess electricity you export to your DU.

Q12. Please give an example of a DU’s blended generation cost, say for the billing month of November 2013?

A12. Using Meralco’s generation costs for November 2013 (as downloaded from its website), its blended generation costs, excluding other generation adjustments, for November 2013 is highlighted in yellow (see table).

double click to enlarge image

Q13. Will I incur additional charges if I avail of net-metering?

A13. Yes, DUs shall impose a net-metering charge to all customers who avail of net-metering equivalent to their existing ERC-approved Php/customer/month supply and metering rate based on the exported energy as registered in the export meter. This net-metering charge shall cover the DU’s incremental costs related to system enhancement and additional meter reading and other operating costs. The DUs may also apply before ERC a different schedule of net-metering charges subject to ERC approval after due notice and hearing. Meantime, the net-metering charges cited above shall prevail until a different schedule of net-metering charges is approved by ERC.

Q14. Please give a simulation of how my electric bill would look like if I am a net-metering customer with a 2kW solar-powered facility installed on my rooftop?

A14. See assumptions and simulated electric bill below:

Assumptions:

Rated Capacity of Solar Rooftop                                     2.00 kW

Yield @ 100% Capacity Factor (2kWx720hrs)                1,440 kWh

Yield @ 16% Capacity Factor 1,440x16%                       230 kWh

Own Use @ 60%                                                                 138 kWh

Net Export @ 40%                                                               92 kWh

Double click to enlarge image

Q15. Are all customers ideal candidates for net-metering?

A15. Not all DU customers are ideal candidates for net-metering. Customers with demand-related (kW) charges may not be ideal candidates for net-metering because net-metering displaces only energy related (kWh) charges.

Be that as it may, customers whose peak demand of electricity coincides with the availability of the RE resource may also stand to benefit from net-metering even if he has demand-related (kW) charges. This is because his RE production can potentially reduce his coincident peak demand for electricity.

Q16. Who then would be ideal candidates for net-metering?

A16. Customers with pure energy-related charges will benefit from net-metering.

As mentioned above, customers whose peak demand of electricity coincides with the availability of the

RE resource may also stand to benefit from net-metering even if he has demand-related (kW) charges

because his RE production can potentially reduce his coincident peak demand for electricity.

Q17. What is the optimum size of an RE facility should I install in my premises?

A17. If you consume all of your RE production, you avoid 100% of the retail rate of your electric bill. If you export any excess RE to your DU, you only offset the blended generation cost (or weighted average power production cost) of your DU. This is about 40-45% of the retail rate of your electric bill. So for an RE facility like a solar roof top system, the optimum capacity that you should install in

your premises should not exceed your daytime peak demand for electricity so that you can maximize your savings/avoided cost on electricity, and shorten to the extent possible the payback period of your investment in the solar roof top facility.

***

EastGreenfields post notes:

In EastGreenfields, we can give you proposals with simulated month by month billing schedule.

Email us for details: inquiry@eastgreenfields.com

or visit our website

www.eastgreenfields.com

Batteries in Series & Parallel

HP Issue date: 

10/10/12

Hugh Piggott

Connecting two battery banks of different amp-hour capacity together in series is a bad idea. The problem is that the battery charging controls will operate based on the average battery voltage and the two batteries will have very different voltages because their capacities are different. The 100 AH battery will become fully charged long before the larger one. The combined voltage will rise, but by the time the controller turns off the charging sources, the 100 AH battery will be overcharged. Meanwhile, the 200 AH battery will not get fully charged. When the bank is being discharged, the 100 AH battery will go flat and its voltage will fall well before the 200 AH battery. The inverter will eventually cut out but not before the 100 AH battery is excessively drained.

Connecting two banks with different capacities in parallel is technically fine since the batteries will be operating at the same voltage. Charge and discharge current will be shared, based on capacity. It is best if the batteries are of the same type and age. For example, avoid combining a sealed (gel or absorbed glass mat) battery with a flooded (conventional) battery because they have different charging setpoints. Broadly speaking, you can parallel batteries without problems, and the charge controller will look after them. Just make sure you give them plenty of charge. If the system tends to operate at less than a full state of charge, adding new batteries to old will probably just result in the old ones pulling the new ones down and everything getting sulphated.

Choosing the Best Batteries for RE (Solar)

Choosing the Best Batteries

HP Issue date: March 2012

By: 

Chris LaForge

Whether you need batteries to store energy for your off-grid home, or you want backup power to keep the lights on when the grid goes down, understanding the different battery specifications will help you select the ideal batteries for your application.

To choose the right battery, you first need to know what you are trying to accomplish. What system type are you working with—off-grid or grid-tied? Where will the battery bank be located? How much maintenance are you prepared to do? And how often (or not) do you want to replace your batteries? The answers to these questions will dictate which batteries make the most sense for your renewable energy system.

Budget also plays a big role in which batteries you choose. Buying batteries is a long-term investment, and skimping on these important components can cripple a system. Getting it right the first time will pay off in performance and longevity. However, simply buying the most expensive battery does not ensure you are meeting the needs of your renewable energy system. For your system to operate and perform well, it is crucial to understand the various battery specifications and how they relate to RE system design.

Batteries used in an RE system can be broken down into two basic categories: heavy duty/commercial and industrial. A common heavy duty/commercial-type battery bank may be comprised of several 6 V, 390 AH (L-16 type) batteries. An industrial battery pack will usually be large 2 V cells (with thicker lead plates) pre-wired to 12, 24, or 48 V and encased in a large metal housing. You will pay more for the industrial battery bank than you will for the equivalent battery pack made of heavy duty/commercial batteries, but you gain longer battery life and a better warranty. 

If you are working with an installing dealer, they often have preferences about which batteries they will use. For example, some installers will only work with L-16 type batteries because they are the largest that they can readily move by themselves—each L-16 battery weighs around 120 pounds, whereas industrial batteries can weigh thousands of pounds, making them difficult to maneuver without disassembly. If you have no experience with batteries, shorter-lived, less-expensive batteries may be a better choice to get you up to speed with battery operation. But some installers will still lean toward the expensive industrial battery packs because they want to minimize battery replacement. This can be especially beneficial in an off-grid setting where just getting to the site may be difficult—much less moving the old batteries out, getting the new ones in, and having to haul the old ones away for recycling. However, industrial batteries are only a wise investment if you are confident in your ability to maintain the battery bank.

Choosing Your Batteries

As with any RE system investment, your best bet will be to identify your true needs and design a system around them. Grid-tied battery backup systems generally use low-capacity  banks made up of sealed, non-industrial batteries that will meet your needs for running critical loads like refrigeration and lighting during power outages. They are generally designed to stay at float most of the time with only occasional cycling, and are often made with calcium alloyed with the lead which helps lower battery self-discharge losses.

To properly size a backup battery bank, compute your critical load profile to determine daily watt-hour consumption during power outages. That number can often be your guide for the correct battery size. Most grid outages are less than one day, and a battery bank sized to be discharged to 50% of capacity by the critical load profile will meet most needs nicely.

If you’re off grid and rely on your batteries to meet all your electrical loads, buy a long-lived battery and be prepared to maintain it well. These systems—which cycle the batteries daily—use batteries with a lead-antimony alloy, which performs better under conditions of regular cycling. 

Typically, off-grid battery banks are sized by considering the required “autonomy”—the number of days that the battery will provide for the loads before reaching 50% depth of discharge (DOD). Off-grid systems usually size a bank to provide two to four days of autonomy. For example, if your load profile requires 5,000 WH per day, you’ll want a battery that stores 10,000 WH to achieve one day of autonomy. Four days of autonomy would require a 40,000 WH battery capacity.

Off-grid system designer opinions on maximum DOD vary widely. Some prefer to keep the depth no greater than 20%, while others have no fear of going below 50%. The deeper the regular discharge, the fewer cycles a battery will give you before needing replacement. So if you do not mind swapping your battery bank more often, go with a deeper discharge—it will save you money up front. But if swapping batteries into and out of your system is a royal pain, you might prefer maximizing battery life by buying a higher-capacity battery. For the design choice that will save you money in the long run, calculate the savings from buying fewer batteries up front, plus the cost of more frequent battery replacement (higher DOD)—versus more batteries up front, with fewer replacements (lower DOD).

...And Don’t Forget

To maximize battery life, batteries need to be properly maintained by:

• Making sure the batteries get completely recharged at least once a week by RE generation and/or supplemented with backup generator or grid charging

·                                 Monitoring the electrolyte and adding distilled water when needed if flooded batteries are used

·                                 Keeping the terminals and interconnections clean by removing built-up corrosion and keeping the battery tops clean and dry

·                                 Equalizing the batteries four to six times a year to remove surface sulfation from the lead plates

Specs Definitions

Manufacturer. Battery manufacturers build batteries for many different applications. Historically, RE systems used batteries originally designed for other applications, such as powering electric golf carts. Today, many battery manufacturers list which of their batteries are appropriate for RE systems. All battery manufacturer Web sites listed in this guide, with the exception of FullRiver Battery, list batteries specifically for use in RE systems.

Model name. These letters and numbers are used by the battery manufacturer to “name” a group of batteries that have similar characteristics, and distinguish them from the company’s other battery lines. It is important to not use batteries with differing model numbers within the same battery bank, as mixing different battery types can create an imbalance within the pack which leads to poor system performance and may cause premature battery bank failure. 

Battery type. Flooded lead-acid (FLA) batteries are the most common type used in RE systems, particularly off grid. They are the least expensive per capacity and, if well maintained, can have a relatively long life span. However, they require the most maintenance. Distilled water needs to be added to the cells on a regular basis, depending upon how often and how deeply the bank is cycled, and upon battery charging regimens.

Valve-regulated lead-acid batteries (VLRA, a.k.a. sealed batteries).  Two general types of VRLA batteries are available for RE systems—absorbed glass mat and gel cells. Absorbed glass mat (AGM) lead-acid batteries are similar in chemistry to FLA cells. In their construction, glass mats, placed between the lead plates (anodes and cathodes), allow the electrolyte to be suspended close to the plates’ active material. These sealed batteries offer the advantage of not needing to be watered and greatly reduced gassing during charge cycles. This type of construction—adding glass mats, sealing the cells, and constructing the plates to operate with less electrolyte—increases cost while potentially shortening life span.

Gel cells use a “gel”-type electrolyte—with a silica additive that causes the liquid to stiffen. Gel-cell batteries are also sealed, which means no water to add—less maintenance and less gassing. However, because lost electrolyte cannot be replaced, they also have a shorter life. They are typically more expensive than FLA or AGM batteries.

Because AGMs can’t be watered, they have to be charged more lightly to avoid using up the finite amount of electrolyte they contain. Gel cells also aren’t watered but need to be charged even more lightly to avoid drying out the cell, which will kill it. 

So why would you ever choose shorter-lived, more expensive batteries like AGM or gel cells? The reasons vary, but often portability, poor battery area ventilation, and maintenance are factors. AGM and gel cell batteries have no liquid electrolyte to spill, so they can be a good choice for mobile systems. And because they hardly gas, they can work well in places where adequate ventilation for FLA batteries isn’t possible. Because they are freeze-resistant, they may be a good choice in applications where extreme cold is a factor.

AGM batteries are often the best choice for grid-tied applications with battery backup, since they are designed for float or standby applications. Because low-capacity battery banks are typical in backup applications, both decreased cycle life and increased cost can be offset by the fact that these batteries are rarely cycled. Plus, users with grid-tied systems are usually less inclined to pay attention to the battery maintenance, since they are also unaccustomed to “maintaining” their grid power. Finally, VRLA batteries will outlast FLA batteries that are not maintained properly (i.e. not watered regularly). If batteries are to be deeply cycled (50% to 80% DOD), gel-cell batteries may offer a longer life (more overall cycles) than AGMs.

Nominal Battery Voltage. Lead-acid batteries are built from individual cells with a “nominal” voltage of 2 V. Battery packs for RE systems are made up of combinations of cells to achieve nominal battery bank voltages of 12, 24, or 48. When designing small systems (loads less than 1,000 WH per day), 12 VDC is often selected as a nominal battery bank voltage if that system is not projected to grow. So a system for a hunting cabin that isn’t going to become a vacation home will keep battery costs down by having this low-voltage design.

For systems with heavier load profiles, larger (and more electrically efficient) battery voltages of 24 and 48 are commonly used. With commercial deep-cycle batteries (like golf cart and L16), the basic unit is often a 6 V battery made up of three, 2 V cells. In the medium-to-large systems, these 6 V units are typically combined in series (four for a 24 V string; eight for a 48 V string). To get greater AH capacity at that voltage, additional strings are then paralleled or higher-capacity batteries are selected.

Amp-Hour Capacity. The sizing of the battery bank depends on the storage capacity required, the maximum discharge rate at any time, the maximum charge rate, and the temperatures at which the batteries will operate.

A battery’s storage capacity—the amount of electrical energy it can hold—is typically expressed in ampere-hours (amp-hours, or AH) at a certain discharge rate. One AH represents a flow of electric current of 1 amp for 1 hour. A battery is like a bucket—the larger your “bucket” is, the more AH it can hold. Hence, the larger the AH value of a battery, given a particular discharge rate, the more storage it offers.

Often there’s a choice of selecting a battery with either higher voltage and lower AH, or lower voltage and higher AH. How do you know which is most appropriate for your application? In general, limit the number of battery series strings in parallel to three or less (two are better, and one is ideal). This reduces imbalances introduced by having multiple paths for the current to follow and extra electrical resistance created by paralleled battery cables. In applications where more AH are needed, buy lower-voltage, higher AH batteries so that several low-voltage batteries can be wired in series and the number of paralleled battery strings can be minimized.

The denoted AH capacity of a given battery depends on the rate at which it is being discharged and the amount of time it takes to discharge it. Large industrial batteries, i.e. for forklifts, are often rated at the “6-hour” rate, indicating a high current discharge rate, which brings the battery to its terminal voltage (often at 80% DOD) in 6 hours, about the length of a forklift’s working shift. For RE systems, a 20-hour rate is typically used, because that is closely aligned with the more modest discharge rates that bring the battery to a terminal voltage (again, often at 80% DOD) over 20 hours—more closely approximating daily home use before recharging.

For converting 6-hour rates to an RE system’s more common 20-hour rate, multiply by 1.24. Using this calculation, a 100 AH, 6-hour rating offers 124 AH at the 20-hour rate.

Bulk Charge Set Point Voltage. When charging batteries, the goal is to put as much current as possible into the battery as efficiently as possible. But charging a battery too quickly can cause heat to build up in the battery, as well as excessive gassing, and can shorten the battery’s life. To keep from harming the battery during charging, charge controllers used in RE systems limit the charge rate based on the batteries’ voltage. As the cell voltage increases, the charge rate (the number of amps allowed in) is reduced to prevent overcharging.

The initial phase when all available current is allowed into the battery is referred to as the “bulk” charge phase. Once the battery has reached its initial bulk-charge voltage, the charge controller will hold the voltage there for a programmed period of time (often 2 hours)—the “absorption” charge phase. This is done to assure full charging throughout the many cells of the battery. Note that the set points listed in this guide are per cell, so you will need to multiply it by the number of series-connected cells to determine the appropriate battery charge set points. For example, if you were to use four batteries (6 V each, wired in series for a 24 V configuration) and the bulk charge set point voltage range is 2.4 to 2.49 V for your battery’s cells, the ideal battery bank bulk-charge voltage set point would be between 28.8 and 29.88 V (3 cells per battery x 4 batteries x 2.4 to 2.49 V).

Float-Charge Set Point Voltage. After the absorption period, the charge controller ramps down the charging current to achieve the “float” phase, which is a lower voltage that greatly reduces the batteries’ gassing while still keeping the battery full. To continue the example, the float-charge set point voltage range is 2.20 to 2.23 V for each cell. With 12 cells total, the ideal battery bank float-charge voltage set point for this particular battery bank would be between 26.4 and 26.76 V.

Both AGM and gel-cell batteries will not tolerate voltages that are as high as FLAs. The charge controller’s bulk and float set points must be programmed appropriately to avoid damaging these batteries.

Equalization Charge Set Point Voltage. An equalizing charge cycle is a controlled overcharging of the battery bank to make sure all cells get charged, and to remove sulfate ion bonds on the batteries’ plates and to regain battery capacity—before permanent bonds develop. First, the battery is charged to full capacity by completing a bulk and absorption charge cycle. Then the battery is charged for an extended period of time, typically 6 to 12 hours, at a C/20 rate (charging amps equal to battery’s AH capacity divided by 20). By controlling the charge rate at C/20, the battery is kept from harm. (Uncontrolled overcharging can warp the batteries’ plates, causing it to short out and possibly explode.)

Equalizing an FLA battery is essential to maintaining battery life, but can be difficult to achieve with the limited current available from a PV array. In off-grid applications, a backup engine generator is often used to equalize the batteries through a charger. Off grid, the use of household loads is generally limited during equalization to make sure enough current is available. In utility-tied systems with batteries, the grid substitutes for a generator.

Using the example of the four-battery bank (6 V each, wired in series for 24 V) and an equalization charge set point voltage range between 2.5 and 2.67 V per cell, the ideal battery bank equalization charge voltage set point for this particular battery bank would be between 30 and 32.04 V.

It is commonly believed that sealed batteries should never be equalized, yet some sealed battery manufacturers will provide an equalization voltage set point for their batteries. It is important to note that these values are usually the same as the bulk voltage set point for that battery. Typically, equalizing sealed batteries means merely extending the absorption period for a longer duration than normal. Additionally, sealed battery “equalization” is usually done only if the battery is showing signs of premature capacity loss (i.e., not lasting as long as normal on a charge), and is not part of routine battery maintenance. Regardless, equalization is very battery specific, so it is important to find appropriate voltage set points and charge current ranges for your particular batteries.

Dimensions. When you’re designing your battery bank, the size of the batteries—their length, width, and height—determines the size of the containment that you’ll need to buy or build. In addition to considering the dimensions of the  batteries, it’s a good idea to leave 1/2 to 1 inch of space between each battery. This will help keep the individual batteries operating at the same temperature and allow them to shed heat during heavy charging regimes.

Weight. Even the smallest batteries used in RE systems can weigh as much as a Labrador retriever—50 to 60 pounds. The really big batteries can weigh as much as a small horse. So, adequate trucks, skids, pallet jacks, and forklifts all become more important in moving batteries safely as the bank grows in size. You’ll need to make sure your floor and/or rack is stout enough to support the total weight of the bank.

Warranty. Manufacturers generally guarantee their products to be free of defects and perform as specified for a set period of time, and will replace defective units during this time period. Many manufacturers offer one-year free replacement with additional prorated warranties for two or three years. During this period, the distributor will replace the failed unit for a percentage of the replacement cost.

Access

Batteries have enabled Christopher LaForge to live and work for more than 20 years at his off-grid, sun- and wind–powered homestead, SunFarm, in Bayfield County, Wisconsin. He is an ISP-affiliated PV instructor with the MREA, a NABCEP‑certified PV installer, and a member of the NABCEP board of directors.

December 2013 MERALCO power rate

December 2013 MERALCO power rate

The December generation cost for MERALCO is pegged at Php7.6673 per kW-hr across all consumption level (50-5000 kW-hr) or a cost increase of 35% from November generation cost of Php5.6673 per kW-hr

Graph 1:  2011 to 2013 the cost for 300 kW-hr for the month of December

Graph 2: Annual electricity rate as of December 2013 for all level (50-5000 kW-hr)

Graph 3: Monthly electricity rate for 300 kW-hr level from January to December

Source: Meralco website

http://www.meralco.com.ph/customer/page-cusCare-billRates.html#

***

EastGreenfields Enterprises is a Solar Power Generation provider.

Please visit our website: www.eastgreenfields.com

Net Metering for the Visayas

Distribution utility encourages net metering

By Marigold P. Lebumfacil/BRP (The Freeman) | 

CEBU, Philippines - The Visayan Electric Company is requesting the public to embrace net metering during a forum yesterday at the Ramon Aboitiz Foundation Inc. Plenary Hall.

Sebastian Lacson, VECO chief operations officer, said the basic concept of the net metering is that if the consumption exceeds generation, customers pay for net per kilowatt-hour consumed. However, if the generation exceeds consumption, customers receive credit in their bill for net excess generation, explained Lacson.

He encouraged consumers to adopt the said changes as this is indeed a beneficial one.

“We are happy embracing net metering. So we encouraged the customers to also adopt this practice. This will come out very soon,” Lacson said.

This is also VECO’s way of adapting to the government project regarding feed-in tariffs on the renewable energy use. But this one is quite unique since the different households can put up a solar panel in their respective homes and they can have self-generation of power without using power coming from VECO.

Lacson also revealed that they will be signing a memorandum of agreement with a Belgian distributor of solar panels soon, to actively push for solar panel technology.

Aside from net metering, Lacson also shared that they already piloted the pre-paid metering system, but this is not yet available to the public since they still need to iron out everything.

“We are deploying these (pre-paid meters) but we are still testing it as of the moment. We will make it available soon after we can iron out everything,” Lacson said.

With the prepaid metering system, VECO uses the Standard Transfer Specifications platform, in order to support the prepaid electricity scheme. Lacson said this offers consumers who are budget conscious and also people operating apartments and boarding houses a chance for a cheaper bill.

Aside from the two, they also have smart metering wherein VECO can read meters and disconnect a line remotely. They can also be informed right away if there is an outage.

Lacson is also optimistic that nine months from now, people can see a much more improved Osmeña Boulevard with its P50-million underground cabling system project from the Capitol to Fuente Osmeña as they have transferred overhead power lines to below street level.

As of June 2013, VECO is serving 358,166 customers across 672 square kilometers with 433 megawatts in Metro Cebu.  (FREEMAN)

November 2013 MERALCO power rate

November 2013 MERALCO power rate

The November generation cost for MERALCO is pegged at Php5.6673 per kW-hr across all consumption level (50-5000 kW-hr) or a cost increase of 21% from November generation cost of Php4.6832 per kW-hr

Graph 1:  2011 to 2013 the cost for 300 kW-hr for the month of November

Graph 2: Annual electricity rate as of November 2013 for all level (50-5000 kW-hr)

Graph 3: Monthly electricity rate for 300 kW-hr level from January to November

Source: Meralco website

http://www.meralco.com.ph/customer/page-cusCare-billRates.html#

***

EastGreenfields Enterprises is a Solar Power Generation provider.

Please visit our website: www.eastgreenfields.com

Off or On Grid?

Off or On Grid?

By: Ian Woofenden

HP Online 

Dreaming of cutting the cord and getting rid of the big bad utility? Perhaps you should think again. Renewable electricity has lots of benefits, but stand-alone (off-grid) systems are more expensive and complex, and require more maintenance than batteryless grid-tied systems. And there are other big advantages to installing renewable energy systems on the grid. Before you make your decision about whether to be off grid or not, let’s take a closer look at the pros and cons.

System Types

Three basic categories of renewable electricity systems are available today (though the future may hold more!).

Stand-alone off-grid systems are completely independent of the utility grid. With the exception of direct-use systems like water pumping or PV-powered ventilation, stand-alone RE systems must have batteries to provide energy storage during times of low input or high usage.

Battery-based grid-tie systems are quite similar to stand-alone systems. They also use batteries, but they are connected to the utility grid, so they can send out to the grid any surplus electricity generated by the RE system, and use utility electricity when needed.

Batteryless grid-tie systems are the simplest of all systems, having only the energy generation technology (be it PV modules, or a wind or microhydro turbine) and an inverter connected to the utility grid. They do not have batteries, which points to their primary drawback—they have no backup capability. When the grid goes down, these systems also shut down.

Off-Grid Advantages

Independence is chief among the reasons for wanting an off-grid system where the grid is available. Off-grid systems are not subject to the terms or policies of the local utility, nor are system owners subjected to rate increases, blackouts, or brownouts.

If you’re shopping for rural property, you’ll probably find that off-grid parcels are less expensive. Most people aren’t ready to take on being their own utility, and the land is priced according to this value system. Being off-grid can also be cheaper than getting a utility line extended to a property. But bear in mind that with off-grid renewable electricity systems, there are up-front and ongoing costs.

Off-grid systems may have a slight edge over grid-tied systems when it comes to expandability. While both are modular, it’s often easier to grow an off-grid system as you can afford it. In fact, many off-gridders with limited incomes find this to be the norm—gradual weaning from fossil-fueled generators by adding more renewable capacity. With lower array voltages (12 to 72 VDC nominal), one to four modules can be added at a time. Batteryless grid-tie systems run in the 150 to 600 VDC range, and specific inverters have voltage windows and efficiency curves, so that adding to them requires more modules and, possibly, another inverter.

Unless you can afford an oversized system, off-grid systems tend to force you to use electricity efficiently. This is a big advantage if you also hold environmental values. Some of the most energy-efficient homes in the country belong to off-grid folks. When you have to make all your energy with only the available resources at your site, you think about how to use that energy wisely.

There are many less tangible advantages of being off grid as well, including the satisfaction and peace of mind that goes with using electricity responsibly. And maybe your neighbors will begin to think you are way ahead of your time.

Off-Grid Disadvantages

When you make the decision to go off grid, you take on the duties of the cursed utility you were trying to avoid. My experience is that you tend to curse them less and appreciate them more as you tackle these responsibilities.

First and foremost, making all of your own electricity is costly. If you are already on the grid, it’s unlikely that installing an off-grid RE system will provide you with cheaper electricity, unless your area has generous incentives, very high utility rates, or both. (Note that most financial incentive programs apply to on-grid systems and do not apply to batteries.) Of course, if you’re a long-term thinker, this changes the picture. But most people conclude that “going off grid” to save money is not a winning concept. With existing off-grid property, you need to weigh the cost of line extension against installing an off-grid RE system. In some areas, utility line extension can exceed $20 per running foot.

System maintenance and troubleshooting are serious, ongoing responsibilities with off-grid systems. When you pay your utility bill, you’re paying for those hard workers in business suits and coveralls to take care of things. If you are the utility, you have to do the work all by yourself, plus buy the coveralls.

Off-grid systems use batteries to store electricity and provide it for your home, but batteries don’t last forever. In fact, they will need replacement every five to fifteen years (typically less than ten, unless you have deep pockets for high-quality, industrial-type batteries). A minimal bank of batteries will cost at least $1,000, and long-lasting industrial batteries for the same application might cost three to four times that much. And it’s not just the cost in dollars that’s a disadvantage. There’s maintenance and replacement time, aching backs from lifting that heavy metal, and perhaps labor cost—and then there’s the environmental cost of making, moving, recycling, and replacing all that lead.

Batteries have another, less tangible cost, and that’s energy waste. At their best, batteries are 90% efficient. That means if you put in 10 kilowatt-hours (kWh), you will get out less than 9 kWh. As they age, their efficiency drops further, and they are also affected by temperature. All this adds up to more energy waste the larger, older, hotter, or colder your battery bank is.

In comparison to grid-tied systems, stand-alone systems have another serious drawback—wasted surplus energy. When a grid-tied renewable electricity system makes more than the homeowners use, the surplus is fed to the utility, creating an energy credit and allowing the system to always run at full capacity. Nothing is wasted, and the grid is figuratively (not literally) 100% efficient—you get credited for all that you throw their way. When you’re off grid, your surplus must be used or it will be wasted. With most off-grid PV systems, the array simply gets turned off by the controller when the batteries are full, so the energy is never generated. With most wind and hydro systems, the excess energy is shunted to a dump load, typically an air- or water-heating element. Savvy off-gridders are aware of their system operation, and change their energy-use habits when there’s a surplus—like choosing to do laundry in the middle of the day. But it’s not automatic, and it takes some social adjustments to switch from energy sipper to energy gorger depending on the weather.

Most off-grid systems need a backup engine-generator, and this is another big disadvantage of these systems. Generator electricity is expensive when you calculate the cost of purchasing, fueling, and maintaining these dirty, noisy machines. And if you buy a cheap model, you might end up with what veteran off-gridder and RE installer Roy Butler calls an “800-hour throwaway” and have to replace it sooner than you wished.

If living off grid sounds like a bit more trouble than you expected, good! I’d like you to be successful with your renewable energy plans, and being realistic is a good first step. My family moved off grid in 1981, and my wife and I have raised a raft of kids and run several businesses from home, so I know that it’s not always a picnic. We’ve been through multiple generators, and have had hard times when we had to wait for the weather to change before doing the laundry. The social and familial implications of living with a variable energy source shouldn’t be underestimated!

Living off-grid can be satisfying, but it’s also a big responsibility. It’s necessary to be willing to flex your electrical activities with the changes in the weather, or be willing to start up a fossil-fueled generator whenever nature is not cooperating with your energy plans. If you’re a city dweller who gets impatient when the traffic light takes a while to change, imagine how you’ll handle waiting for the sun to come out or for that mechanic to fix your generator.

On-Grid Advantages

Using renewable energy on the grid avoids most, if not all, of the disadvantages of being off grid. The utility is like a big, 100% efficient battery that can absorb all your surplus energy. In addition, you can lean on it as hard as you want to for as much additional electricity as you might need. If you can’t afford a renewable-electric system large enough to supply all your needs, you can install whatever portion you can afford. If you’re off grid, you have to make it all, one way or another, and if you’re strapped for cash when you’re putting in your system, you’ll end up making a lot of it with fossil fuels. When the grid uses fossil fuels, at least it uses them more efficiently, and with less noise and pollution than a home generator.

With grid-tied renewable energy systems, there is no absolute need to conserve electricity or change your lifestyle. You can choose to live the same way you lived before you installed an RE system. Your system will offset some or all of your usage, and your daily life can continue unchanged.

If you decide on a grid-tied system with battery backup, you can have the best (and some of the worst) of both worlds: You can have the independence and backup of a stand-alone system, still be able to use at least some energy during utility outages, and have the ability to sell your excess energy to the grid.

For all these system types, investing in a PV system also means locking in the long-term pricing of your electricity. With a photovoltaic system, you are buying 40 to 50 years of electricity at a fixed price, while maintaining the benefits of being on grid.

On-Grid Disadvantages

One major disadvantage of having a grid-tied system is that you have less incentive to conserve. That inviting wall receptacle will take whatever you plug into it, and no “depleted battery” warning will sound when you use a lot of electricity. If you can manage to bring an off-grid mind-set to your on-grid home, you’ll make the most of your RE investment.

With batteryless systems, you’ll have no backup. In most cases, this is not a very serious drawback. The utility grid is quite reliable in most urban places in the United States, with outages occurring only a few times a year for a few minutes to a few hours. But if you have frequent or long outages or critical loads, a batteryless system will frustrate you and maybe even cost you an occasional freezer full of food.

However, battery-based grid-tie systems typically only provide modest backup. To power all of your loads during an extended outage when there’s no sun would require a very large battery bank, which would be expensive and make for a less efficient renewable energy system.

For all grid-tied systems, you also have interconnection red tape. This can range from simple to onerous, depending on the authorities and utility you have to deal with. In places where RE systems are becoming common, there may be a greased path through your inspection agencies and utility, once you know the right people to deal with and the right forms and procedures. If you’re pioneering a new path, you might run into a lot of roadblocks, such as public servants or utility personnel who are ignorant of these systems, or burdensome gear or paperwork requirements.

Weighing the Costs

So how do you make the choice between being on grid and off grid? This is a personal decision, based on finances and personal values. First, weigh the costs. A battery-based system generally costs about 30% to 40% more than a batteryless grid-tie system, and maybe as much as 50% more, depending on the battery bank size and other components. The other major consideration is the cost of utility-line extension. This can range from zero for properties close to existing utility lines to hundreds of thousands of dollars for properties that sit a long way from the line. Get quotes from solar contractors and from your utility, and then crunch the numbers.

Values are a bit harder to evaluate objectively. I know people who were faced with $25,000 line extension costs to get utility electricity to their property. They opted to stay off grid and, in the end, invested more than $75,000 in their wind- and solar-electric systems. For this, they get satisfaction, independence, and no utility bills. Obviously, the up-front cost was not their highest consideration—they have other values. But they invested a lot of money and time initially, and will have the continued investments in time and money to keep their systems running. Others may decide to spend anywhere from a few thousand to tens of thousands of dollars for the reliability, efficiency, and convenience of having the grid, even if they invest in an RE system that will offset all of their usage and bills.

From the perspective of more than 25 years of off-grid living, my advice is not to unplug from the grid if it’s there. Of course, there are exceptions to every bit of advice, and if you live where net metering (selling back to the grid for credit) is not available or monthly base charges are high, you have a different situation. But in general, “greening up” the grid with your renewable electricity will benefit you, the environment, and your community better than cutting the cord.

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Ian Woofenden has lived off grid with his family in Washington’s San Juan Islands for more than 25 years.