helping you get started with green energy.

Welcome to the Solar Power Forum

Hello,

I wanted to kick this forum off by asking a question, why are you interested in solar photovoltaics?

▶ Reply to This

Replies to This Discussion

Permalink Reply by Martin Herzfeld on September 25, 2009 at 6:46pm: Briefly, specifically, for instance if ~205 watt modules STC, http://www.gogreensolar.com/products/sanyo-hit-205-watt-solar-panel...

Maximum Power Voltage (Vpm): 56.7 Volts
Maximum Power Current (Ipm): 3.62 Amps

Power = Voltage * Current => 56.7 V * 3.62 A = > ~ 205 watts at 25 degrees C, 1kW/m2, ....

Two modules series:

Power = Voltage * Current => ((56.7 V) * 2) * 3.62 A = > ~ 410 watts at 25 degrees C, 1kW/m2, ....

Two modules parallel:

Power = Voltage * Current => (56.7 V) * (2 * 3.62 A) = > ~ 410 watts at 25 degrees C, 1kW/m2, ....

Why series instead of parallel? Simple answer - because of power loss. On the DC side, Power Loss = I(mp) 2 * Resistance. The National Electrical Code Chapter 9, Table 8 provides resistance distance.

IF you notice, since, the power loss is a factor of current, if the current increases, the power loss increases. Therefore, simply 410 Watts not equal to 410 Watts. If the calculations were for voltage drop, you find the voltage drop would increase as a factor of current. As a result, the best practices, would be to increase the number of modules in the photovoltaics source circuit based on the V(oc) and NEC 690.7 with above the V(min) of the inverter and MPPT at a percentage to factor Light Induced Degradation (LID) over time, hot climates, other other factors.

Also the inverter on the AC side would be near the point of connection with regards to the voltage drop a ~1%. Although the voltage drop on the DC side may be 2-3%, would be for administrative purposes, and the method is to determine the power loss for the balance of systems (BOS), where BOS + Array = System.

From a financial perspective, integrators maximize panels. From a customer perspective, would suggest consider maximizing modules. Also the value of energy may be based on azimuth and the solar noon and may be based on time or usage.

What do you think?; ▶ Reply to This

Permalink Reply by dexter jerome bernardo on January 17, 2010 at 7:45pm: What is the advantages of solar generator?
Solar generator is an environmental friendly equipment that can use anywhere. You can save the earth by having good equipment like a solar generator. What are the advantages of a solar generator? If you don't know, check out sunpowerport.com. The featured generator will run most small electrical appliances. It is great for camping or emergency backup. No noise. No fumes. For more details see http://www.sunpowerport.com; ▶ Reply to This

Permalink Reply by Deep Patel on January 17, 2010 at 10:07pm: does your product have a modified sine wave or pure sine wave inverter?; ▶ Reply to This