Paano Paghimo ug I-install ang usa ka Standalone Solar PV System

Paghulagway ug Pag-install sa Solar PV System

Ang modernong lipunan nagdepende sa energia alang sa pangadaghan nga panginahanglan sama sa industriya, pag-init, transportasyon, ug agrikultura, kasagaran gikan sa dili renewable nga mga pinanggugohan (coal, oil, gas). Usa ra sadang kini ang nagdala og pagsalba sa kalibutan, dili parehas nga gipamahagi, ug nagpakita og pagbag-o sa presyo tungod sa limitado nga mga reserve—na nagpapailabot sa pagtumong sa renewable nga energia.

Ang solar nga energia, abundant ug makakaya sa global nga panginahanglan, nakatubag. Ang standalone PV system (Fig 1) naghatag og independensiya sa enerhiya gikan sa utilities. Sumala mahimong tan-awon ang ilang pagplanuhan, paghulagway, ug pag-install para sa pag-abli sa elektisidad.

Pagplano sa Standalone PV System
Pagtantiya ug Survey sa Site:

• Minimization sa Shade: Siguraduhon nga ang site sa pag-install (sa rooftop o ground) walay shading structures, ug walay future nga mga konstruksyon nga moguba sa solar radiation.

• Surface Area: Hukmanon ang area sa site aron masayran ang bilang/laki sa PV panels, ug planohon ang placement para sa inverters, converters, ug battery banks.

• Rooftop Considerations: Para sa tilted roofs, sulbari ang tilt angle ug gamiton ang appropriate mounting aron mapadako ang solar incidence (ideally perpendicular sa panels).

• Cable Routing: Planhon ang routes sa cables (connecting inverter, battery bank, charge controller, ug PV array) aron mapasabot ang cable usage ug voltage drop, balancing efficiency ug cost.

Solar Energy Resource Assessment:

• Insolation Data: Sukat-on o kuha (gikan sa meteorological stations) ang solar energy na natanggap, gamit ang kilowatt-hours per square meter per day (kWh/m²/day) o daily Peak Sun Hours (PSH, oras nga may average irradiance of 1000 W/m²).

• Key Metric: Gamiton ang PSH para sa simplified calculations (distinguish from "mean sunshine hours," which reflects duration rather than energy). Adopt the lowest monthly mean insolation to ensure system reliability during low-sun periods.

Considerations for Standalone PV Systems
1. Energy Demand Calculation

Ang laki sa sistema nagdepende sa load demand, isip hinungdan:

• Daily energy demand (Wh) = Sum of (appliance power rating in watts × daily operating hours).

• Gamiton ang highest daily demand aron balansehon ang reliability ug cost (ensures operation during peak usage, though this increases system cost).

2. Inverter & Charge Controller Sizing

• Inverter: Rated 25% higher than total load (to account for losses).
  Example: For a 2400W load, a 3000W inverter (2400W × 1.25) is needed.

• Charge Controller: Current rating = 125% of PV panel short-circuit current (safety factor).
  Example: 4 panels with 10A short-circuit current require a 50A controller (4×10A ×1.25).
  Note: MPPT controllers follow manufacturer specifications.

3. Daily Energy to Inverter

Account for inverter efficiency (e.g., 90%):

• Energy supplied by battery to inverter = Total load energy / efficiency.
  Example: 2700Wh load → 3000Wh (2700 / 0.9) from battery.

4. System Voltage

Determined by battery voltage (typically 12V, 24V, etc.), with higher voltages reducing cable loss. Example: 24V system.

5. Battery Sizing

Key parameters: depth of discharge (DOD), autonomy days, and system voltage.

• Usable capacity = Battery Ah × DOD.

• Required charge capacity = Energy from battery / system voltage.
  Example: 3000Wh from battery in a 24V system → 125Ah required.

• For 12V, 100Ah batteries (70% DOD):

• Number of batteries = 125Ah / (100Ah × 0.7) ≈ 2 (rounded up).

• Connect 2 batteries in series to achieve 24V system voltage.

So, in total there will be four batteries of 12 V, 100 Ah. Two connected in series and two connected in parallel.Also, the required capacity of batteries can be found by the following formula.

Sizing of the PV Array

• Total PV array capacity (W): Calculated using the lowest daily peak sun hours (or Panel Generation Factor, PFG) and daily energy demand:
  Total Wₚₑₐₖ = (Daily energy demand (Wh) / PFG) × 1.25 (scaling factor for losses).

• Number of modules: Divide total Wₚₑₐₖ by the rated power of a single panel (e.g., 160W).

  Example: For a 3000Wh daily demand and PFG = 3.2, total Wₚₑₐₖ = 3000 / 3.2 ≈ 931W. With 160W panels, 6 modules are needed (931 / 160 ≈ 5.8, rounded up).

• Loss factors (to adjust PFG): Include sunlight angle (5%), non-max power point (10%, excluded for MPPT), dirt (5%), aging (10%), and high temperature (>25°C, 15%).

Sizing of the Cables

• Key considerations: Current capacity, minimal voltage drop (<2%), resistive losses, weather resistance (water/UV proof).

• Cross-sectional area formula:
  A = (&rho; &times; Iₘ &times; L / VD) &times; 2
  (&rho; = resistivity, Iₘ = max current, L = cable length, VD = permissible voltage drop).

• Balance: Avoid undersizing (energy loss/accidents) or oversizing (cost inefficiency). Use appropriate circuit breakers and connectors.