Question 1

How much does a solar system cost in the Philippines?

Accepted Answer

It depends on system size. A basic off-grid setup for lights and fans (500W-1kW) costs around P30,000-P60,000. A mid-range system (2-3kW) that can run a refrigerator and more loads costs P80,000-P150,000. A full-house system (5kW+) with hybrid inverter costs P200,000+. These are DIY prices — professional installation adds 30-50% more.

Question 2

Can I install solar panels myself?

Accepted Answer

Yes, for off-grid and battery-only systems. Off-grid solar does not connect to the grid, so no permits or professional sign-off is required. However, if you want to connect to the grid (net metering), you need a licensed Professional Electrical Engineer (PEE) to sign off on the installation. Even for off-grid, consult a licensed electrician if you're not confident with electrical work — solar systems involve high voltage and current that can be dangerous.

Question 3

How do I know what size solar system I need?

Accepted Answer

Start by listing all the appliances you want to power and how many hours per day you use each one. Multiply watts x hours to get daily Wh consumption. Then: Panel Watts = Daily Wh / Peak Sun Hours / 0.75. For a typical Filipino household with fans, lights, TV, and phone charging, you need about 500W-1kW of panels. Add a refrigerator and you're looking at 1.5-2kW. Our calculator does this math for you automatically.

Question 4

What is TaraSolarTayo?

Accepted Answer

TaraSolarTayo is a free solar calculator and DIY system builder for the Philippines. We help you figure out what size solar system you need, browse compatible components with real prices, and see how to wire everything together. We are not a store — we don't sell anything or earn commissions.

Question 5

What type of solar panel should I buy?

Accepted Answer

Monocrystalline panels are the best choice for most Philippine installations. They have the highest efficiency (20-22%), meaning more watts per square meter of roof space. Polycrystalline panels are slightly cheaper but less efficient (15-17%). Flexible panels are good for curved surfaces but less durable. For a DIY build, stick with rigid monocrystalline panels from a reputable brand.

Question 6

LiFePO4 or lead-acid batteries — which is better?

Accepted Answer

LiFePO4 (lithium iron phosphate) is better in almost every way: lighter, longer lifespan (3,000-6,000 cycles vs 300-500), more usable capacity (80-90% vs 50%), and performs well in Philippine heat. The only advantage of lead-acid is lower upfront cost. Over 5 years, LiFePO4 is actually cheaper due to its longer lifespan. If budget allows, always go LiFePO4.

Question 7

MPPT or PWM charge controller?

Accepted Answer

For small 12V systems under 400W, PWM is fine and much cheaper. For systems above 400W, MPPT is worth the extra cost because it harvests 15-30% more power from your panels. MPPT also allows you to use higher voltage panels with lower voltage battery banks. In the Philippine tropical climate, the efficiency difference between MPPT and PWM is slightly smaller than in temperate climates, but MPPT is still the better choice for larger systems.

Question 8

Do I need a pure sine wave inverter?

Accepted Answer

Yes, for most applications. Pure sine wave inverters produce clean AC power identical to grid power. Modified sine wave inverters are cheaper but can damage sensitive electronics (computers, TVs, refrigerator compressors, LED lights). The only time modified sine wave is acceptable is for simple resistive loads like incandescent bulbs and basic power tools.

Question 9

What wire size do I need for solar?

Accepted Answer

Wire size depends on the current (amps) and distance. For panel-to-controller wiring, 4mm2 (12 AWG) PV wire handles up to 30A. For battery cables, use much thicker wire: 16mm2 (6 AWG) for small systems, 25-35mm2 (4-2 AWG) for larger systems. Always use solar-rated PV wire for outdoor panel connections, not regular THHN. The 2% voltage drop rule: keep voltage drop under 2% of system voltage.

Question 10

How do I mount solar panels on my roof?

Accepted Answer

For GI sheet roofs (most common in PH), use aluminum rail mounting systems with stainless steel bolts and rubber washers to prevent leaks. For concrete roofs, use concrete anchor bolts or ballast-mounted frames. Mount panels at your latitude angle (5-20 degrees in PH) facing south for optimal output. In typhoon-prone areas, use 6 clamps per panel (3 per side) and ensure your mounting system is rated for 250+ kph winds.

Question 11

Is solar installation dangerous?

Accepted Answer

Solar panels produce electricity whenever sunlight hits them — you cannot turn them off. This means there's always a risk of electric shock when working with panels. Battery banks also store large amounts of energy that can cause severe burns or fires if short-circuited. Always wear insulated gloves, use properly rated tools, and never work on a system while panels are exposed to sunlight (cover them with an opaque sheet). For systems above 1kW, we strongly recommend hiring a licensed electrician.

Question 12

How do I protect my solar system from typhoons?

Accepted Answer

Proper mounting is critical. Use heavy-duty aluminum rails with 6 mid-clamps per panel. Bolt through the roof structure (purlins), not just the sheet metal. Rated mounting systems should handle 5,400 Pascals / 250+ kph winds. Before a typhoon, inspect all bolts and connections, disconnect the system if possible, and document everything with photos for insurance. After the typhoon, inspect for loose panels, damaged wires, and water intrusion before reconnecting.

Question 13

How much can I save on my Meralco bill with solar?

Accepted Answer

A 3kW solar system typically generates 350-450 kWh per month in the Philippines. At current Meralco rates (approximately P11-14 per kWh), that's P4,000-P6,000 saved per month. The system pays for itself in 3-5 years for grid-tied setups. Off-grid systems save differently — you eliminate or reduce your Meralco bill entirely, but the upfront battery cost is higher.

Question 14

Is net metering worth it?

Accepted Answer

Net metering lets you export excess solar energy to the grid for bill credits. It's worth it if you produce more than you use during the day, your system is 3kW+, and you can get a PEE to sign off on the installation. The credit rate is based on the blended generation charge (roughly P5-7 per kWh), which is lower than your full Meralco rate. Still, it's better than wasting excess energy. Hybrid systems with batteries + net metering offer the best of both worlds.

Question 15

Can I build a solar system on a tight budget?

Accepted Answer

Yes, but be realistic about what you can power. Under P30,000 gets you LED lights, phone charging, and maybe a fan. P30,000-P50,000 adds a TV and more fans. P50,000-P80,000 can handle a small refrigerator. Start small and expand over time — buy an oversized charge controller and inverter now so you can add panels and batteries later without replacing equipment.

Question 16

Do I need a permit for solar panels?

Accepted Answer

For off-grid systems (not connected to the grid), no permit is generally required in the Philippines. For grid-tied systems with net metering, you need: (1) a Professional Electrical Engineer (PEE) to design and sign off on the system, (2) a building/electrical permit from your LGU, and (3) an application with your distribution utility (e.g., Meralco). The 2026 net metering rules mandate 10-day processing for applications.

Question 17

Is it legal to connect DIY solar to the grid?

Accepted Answer

No. Connecting any power source to the grid without a PEE sign-off is illegal in the Philippines. Unauthorized grid connection (called a 'flying connection') is dangerous — it can electrocute utility workers, damage equipment, and violate the Philippine Electrical Code. If you want grid connection, hire a PEE to certify your system. For DIY builders, off-grid and battery-only hybrid systems are the legal options.

Question 18

What is net metering and how does it work?

Accepted Answer

Net metering is a billing arrangement where your solar system exports excess energy to the grid, and you receive credits on your electricity bill. In the Philippines, it's available for systems up to 100kW. You need a bidirectional meter, a PEE-certified installation, and approval from your distribution utility. Credits are based on the blended generation charge and can be carried over to the next billing period.

Question 19

How often should I clean my solar panels?

Accepted Answer

Every 3-6 months in most areas. More often if you're near a dusty road, construction site, or coast (salt spray). Clean in the early morning or late afternoon — never at noon, as cold water on hot glass can cause thermal shock and cracking. Use a soft brush or cloth with mild soap and low-pressure water. Never use abrasive materials or high-pressure washers.

Question 20

How long do solar panels last?

Accepted Answer

Quality solar panels last 25-30 years. They degrade slowly — about 0.5% per year. A 400W panel will still produce roughly 340W after 20 years. Inverters typically last 10-15 years. LiFePO4 batteries last 10-15 years (3,000-6,000 cycles). Lead-acid batteries last only 2-4 years (300-500 cycles). The panels are the most durable part of your system.

Question 21

Why is my solar output lower than expected?

Accepted Answer

Common reasons in the Philippines: (1) Heat — panels lose about 0.35% efficiency per degree above 25C, and PH rooftops can hit 60-70C. (2) Dust and dirt — up to 25% output loss if not cleaned. (3) Partial shading from trees, buildings, or bird droppings. (4) Wrong tilt angle or orientation. (5) Undersized wiring causing voltage drop. (6) Aging panels. Use a multimeter to check actual output vs rated output.

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