Frequently Asked Questions on Solar (PV)

What is photovoltaics or "PV"?
The term photovoltaic comes from two words: photo meaning light and volt taken from the name of the scientist Alessandro Volta (1745-1827). PV modules/panels convert sunlight into direct current (DC) electricity.

How is electricity generated from the sun?
There are materials called semiconductors that can generate electricity when exposed to sunlight. An example is silicon which can be found in solar panels.

Do solar PV modules work during cloudy and/or rainy days?
As long as there is light available, the PV modules will continue to work but with a lesser output. 

What are the different parts of a PV system?
A PV system is usually composed of the following:

• PV modules or panels
• Battery – for storing energy generated by the PV modules
• Charge controller – to regulate the amount of energy being stored in the battery
• Load – devices needing electricity to run
• Wiring – connects the different parts of the PV system
• Inverter – used for devices that run on alternating current (AC)

For how long can a  PV system last?
A PV system designed correctly and operated and maintained properly usually lasts more than 20 years. The controller, inverter and batteries are usually first to stop working. A properly used battery usually lasts two to three years. A light bulb depending on its quality will last no more than a year.

For what purpose PV systems are usually used?
PV system is a type of renewable energy that provides clean energy and is being used in the Philippines and in other countries. It is usually used to electrify far-flung communities for its cost efficiency.
It can also be used for water pumping and street lighting.

Why should I use PV systems if kerosene lamps are cheaper?
There are many advantages in using PV systems:

1. Health

Unlike kerosene or diesel lamps, PV systems do not emit any poisonous gases that can cause lung diseases.

2. Safety

Kerosene lamps are fire hazards when left unattended. On the other hand, PV systems use compact fluroescent lamps (CFLs) with switches thus users are not exposed to direct fire.

3. Economic and other benefits

CFLs are brighter than kerosene lamps thus children can study at night and parents can continue their economic activities at night.

How are PV systems used?
Like grid electricity, lights are turned on and off using switches. PV modules, charge controllers and batteries are easy to maintain and does not need constant attention. AMORE trains its beneficiaries in the proper use and maintenance of the solar home systems (SHSs).

What devices can be connected to the PV system? Can it power refrigerators, television sets or radios?
The number of devices that can be connected to PV systems depends on its design. AMORE usually installs 50Wp PV modules which generate electricity enough for two to three CFLs. However, the CFLs cannot be used simultaneously for an indefinite time. The charge controller will cut off the CFLs when the battery is nearly empty.

Can any type of light bulb be connected to the PV system?The PV systems require 12 V direct current lamps or light bulbs that can be purchase in hardware or electrical stores in urban centers.

Can two to three batteries be connected to the PV system at the same time?
The number of batteries that can be connected to the PV system depends on its design. AMORE usually installs PV systems designed for one battery only

Can devices be connected directly to the battery?
PV systems upon purchase come with the charge controller. It would be difficult to use a direct connection. It is also not advisable to move the parts of the PV system since this could cause its breakdown.

Can flashlight batteries and mobile phones be charged through the PV systems?
With the AMORE-installed SHSs, battery charging is possible, however, an inverter must be used since flashlight batteries and mobile phones require AC.

How do you dispose the used-up batteries?
The fluid inside the battery is acidic and poisonous. Thus, batteries must be sent to recycling centers and cannot be thrown anywhere. AMORE has a battery disposal program. Beneficiaries can inquire with their local technicians on this program.

Can somebody else use the PV system for charging their batteries?
AMORE-installed SHSs are designed for one household and cannot be lent to other households.

Can the solar panels be transferred to other people’s houses?
When a PV module is not installed properly, this can cause damage to the system. If there is sufficient reason such as emergencies for transfer, then this must be supervised by a technician.

How would you know if the battery is used-up already?
A used-up battery can no longer provide electricity to any of the devices attached to the PV system. To make sure, remember how old the battery is or use the hydrometer to check. Technical problems should always be referred to technicians.

How do you maintain the PV modules?
Keep the PV module clean and clear from shadows caused by trees or roofs. Shadows prevent the PV modules from generating electricity.

How do you maintain the battery?

1. Check the amount of electrolyte in the battery. Slowly add some distilled water using a funnel if electrolyte is low. Be careful when opening the battery caps. Do not smoke while refilling the battery with distilled water.

2. Do not place heavy objects over the battery especially metal objects. This can cause damage to the battery or the battery can short-circuit.

Sources:

• DOE - Energy Efficiency and Renewable Energy: www.eere.gov
• March 4-13, 2005 – AMORE Training on PV by Mr. Herb Wade
• Shell SHS Manual
• AMORE Technical Department