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How Solar Works

The Basics of Solar Energy

• Solar Panels Make DC Power

  • Each panel contains solar cells that turn sunlight into direct‑current (DC) electricity.

  • Panels can be wired in series (adds voltage) or parallel (adds current). Series strings boost voltage for long wire runs but are more affected if one panel is shaded; parallel wiring keeps each string’s output independent.

• Inverters Turn DC into Usable AC

  • Most homes and the grid run on alternating current (AC). An inverter takes the DC from your array and “flips” it into 60 Hz AC at your local voltage (120/240 V in the U.S.).

  • Grid‑tied inverters sync exactly with the utility’s waveform, so any extra power feeds back into the grid; off‑grid inverters include a built‑in charge controller (MPPT) to manage battery charging.

• Grid‑Tied vs. Battery‑Backed Systems

  • Grid‑tied systems have no batteries: you export surplus power to the utility (net metering) and draw from the grid when panels aren’t producing.

  • Battery‑backed (or hybrid) systems include a separate battery charge controller plus batteries, letting you store midday excess for nighttime or outages.

• Panel Types & Durability

  • Monocrystalline (solid black) panels are most efficient and most robust. (For most home projects, go with this -- it will save you money in the long run.)

  • Polycrystalline (speckled blue) panels cost less but have slightly lower efficiency and—because of their crystal structure—are more prone to edge‑chip or crack under stress.

  • Thin‑film panels are light and flexible but deliver the lowest output and require more area.

• Optimal Placement & Tilt

  • Aim panels toward true south (Northern Hemisphere) at a tilt roughly equal to your latitude (e.g., ~40° if you live at 40° N).

  • Keep modules clear of shade—trees, chimneys, even small shadows can disproportionately reduce output.

• Monitoring & Maintenance

  • Many micro-inverters include a simple display or smartphone app showing instant power and lifetime energy. This helps you spot drops in performance (dirty panels, wiring issues) early.

  • If you don’t have inverter‑based monitoring, you can still track your production via your utility smart meter.

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The DIY Team Reccomends

Monocrystaline Vs. Polycrystaline

Monocrystaline = Best

• High Efficiency (20–24.8 %)

  • Commercial monocrystalline modules average 20–23 % conversion efficiency, with flagship models like Aiko’s NEOSTAR 3P54 reaching up to 24.8 %—significantly above polycrystalline’s 15–20 % range

• Very Low Degradation (≈0.4 %/yr)

  • Field data from the National Renewable Energy Laboratory shows modern mono‑Si panels degrade at about 0.4 % per year, so they retain ~90 % of original output after 25 years—slower decline than polycrystalline’s 0.5–0.8 %/y

• Robust Warranties & ROI

  • Premium monocrystalline panels typically carry 25‑year performance guarantees of ≥87 % output. Their higher up‑front cost (≈$0.30–$0.50/W) is offset by greater lifetime energy yield and stronger long‑term ROI vs. cheaper, less efficient alternatives

• Superior Durability

  • The single‑crystal structure resists microcracks and hotspots under thermal cycling, making mono‑Si panels less prone to edge‑chip or mechanical failure over decades

Polycrystaline

• Moderate Efficiency (15–20 %)

  • Polycrystalline modules convert 15–20 % of sunlight to electricity, trailing monocrystalline by 25 – 30 % in peak performance

• Lower Cost (~$0.25/W)

  • With simpler manufacturing, polycrystalline cells sell for around $0.25 per watt—20 – 50 % cheaper than premium mono‑Si panels—making them attractive where space isn’t limited

• Lower Hail Resistance

  • Under standardized hail tests, polycrystalline modules can lose up to 12.6 % of output—three times the degradation seen in monocrystalline panels—making them more prone to breakage in hail‑prone regions

• Series String Vulnerability

  • Poly panels are almost always wired into series “strings” feeding a string inverter. If one panel underperforms (due to shade, damage, or hail), it throttles the entire string’s current until the fault is cleared

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