Practical solar know-how for Tamil Nadu

PM Surya Ghar Muft Bijli Yojana — central government rooftop solar scheme. Tamil Nadu la residential customers ku direct bank transfer ah subsidy varum.

Subsidy slab: 1 kW = ₹30,000 | 2 kW = ₹60,000 | 3 kW or above = ₹78,000 (max cap). Commercial / industrial users ku idhu kedaikadhu — adhukku 40% accelerated depreciation tax benefit irukku.

Apply panna: pmsuryaghar.gov.in la register pannunga, DISCOM (TNEB) approval vangunga, vendor select pannunga (SVN registered), install pannina apparam net meter inspection. Subsidy 30 days la bank account ku credit aagum.

Important: panel + inverter MNRE approved ah irukanum. Vendor invoice, model number, geo-tagged photo ellam upload panna venum.

On-grid: panel → inverter → directly grid ku connect. Battery illa. Extra power TNEB ku export aagum (net metering). Cheapest, fastest payback. Power cut neram solar work aagadhu.

Hybrid: panel + inverter + battery + grid. Power cut neram kuda critical loads (fridge, fan, lights) run aagum. Cost 30–40% jaasthi. Trichy, Perambalur madhri frequent outage area ku worth it.

Off-grid: pure battery, no grid. Remote farm, pump set ku mattum. House ku recommend pannamaatom — battery replacement cost periya.

Rule of thumb: monthly outage 5 hours kammi na on-grid pothum. Hospital, server room, dairy farm madhri continuous operation na hybrid.

1. Panel surface clean pannunga. Dust + bird droppings 15–25% output kammi pannum. Soft cloth + plain water podhum, detergent vendam.

2. Mounting bolts tight ah iruka check pannunga. Heavy wind la loose aagi panel shift aaga vaaippu undu.

3. Inverter display la error code edhuvum varudha paarunga. E-01, E-02 madhri code vandha immediately service team ku call pannunga.

4. Earthing wire + lightning arrester intact ah iruka confirm pannunga. Monsoon la lightning strike risk jaasthi.

SVN customers ku annual free inspection irukku — booking calendar la slot pidikkalam.

Net metering = unga solar produce panra extra power TNEB grid ku send aagum. Month end la 'import - export' calculation pannuvanga. Net consumption ku mattum bill varum.

Tamil Nadu la residential ku 1:1 banking — 1 unit export = 1 unit credit. Commercial ku slightly different tariff.

Annual settlement: financial year end la (March) net export irundha TNEB ku ₹2.50–3.00/unit la sell aagum. Pannaadhu credit lapse aagum, so system size unga consumption ku match panrathu important.

Net meter (bi-directional) TNEB thaan install pannuvanga. SVN team document ready panni feeder inspection, approval ellam handle pannum — usually 10–20 days.

Tamil Nadu la 1 kW solar = average 4–4.5 units/day = ~125 units/month = ~250 units bi-monthly.

Unga last 6 months bi-monthly bills la average units paarunga. Adha 250 la divide pannina venumana kW kedaikum. Example: 750 units / 250 = 3 kW.

Roof area check: 1 kW ku ~100 sq.ft shadow-free roof venum. 3 kW = 300 sq.ft.

Subsidy maximize panna 3 kW pottathuthaan best (₹78k full subsidy kedaikum). Bill periya ah na 5 kW – 10 kW la commercial tariff savings strong ah varum.

Myth 1: Cloudy day la zero output. Reality: 30–60% reduced output, but production continues. Annual yield la monsoon impact ~10%.

Myth 2: Roof la weight thaanga matta. Reality: 1 kW system = ~80 kg spread across 100 sq.ft = 0.8 kg/sq.ft. RCC roof easy ah thaangum.

Myth 3: Battery 2 varushathula pochi pogum. Reality: Lithium battery (LFP) 8–10 yrs warranty, 4000+ cycles. Lead-acid mattum thaan 3–4 yrs.

Myth 4: TNEB power cut pannuvanga because of solar. Reality: net metering legal, TNEB encourage panranga. No penalty.

Myth 5: Solar = AC continuous run pannalam. Reality: kW match aana run pannalam. 1.5 ton AC = ~1.5 kW load, daytime la solar direct ah feed pannum.