What is Solar Energy?
Solar energy is electricity harnessed and converted from the sun. This process is also called photovoltaic (PV).
Considering that Solar Power is the cheapest, causes no pollutants and Malaysia being the tropical country that it is, Solar power seems to be a no brainer moving forward in terms of renewable energy.
Main Components of a Solar Energy System
The beauty of the Solar Energy System is its simplicity, modularity and it’s low cost (relative to other electricity-generating methods). Here are the 3 main components in a solar system:
- Photovoltaic (PV) Panels
- Inverter
- Net Energy Metering (NEM) meter
How Photovoltaic (PV) Solar Panels Work
This part get’s a little technical but let me explain it in layman’s term. The main concept is to get electrons flowing. The flow of electrons is electrical current. Here’s how PV modules make this happen:
A solar PV panel is made out of 2 layers of silicone. The sunnyside modified to be negatively charged (or N-Type), and the bottom side to be positively charged (P-Type).
When sunlight hits the Solar PV panel, here’s what happens:
- Light is a flow of tiny particles called photons.
- These photons hit electrons lose in a photovoltaic cell.
- The knocked loose electron will move towards the N-Type side of the cell and the hole will move towards the P-Type side.
- By connecting an external wire to complete a circuit creates a pathway for the electrons to flow to fill the holes on the other side, thus completing an electrical circuit and generating electricity.
Types of Solar PV Panels
As of today, a typical Solar PV panel dimension is 2m tall, and 1m wide with an area of 2 sqm. There are 2 types of popular Solar PV panels:
- Monocrystalline (better efficiency, 450 W but expensive)
- Polycrystalline (lower efficiency, 350 W but cheaper)
Solar Inverter
The electricity generated from the Solar PV panels is in the form of Direct Current (DC). Which is not the same as the electricity supplied to your home, which is in the form of Alternating Current (AC).
An inverter is an electrical device that converts Direct Current (from the PV panel) to Alternating Current. Here’s how one looks like:
Net Energy Metering (NEM) Meter
NEM is a government scheme for Solar Energy System Users. Here’s how the system works:
Whatever electricity that is generated from the solar PV will be used by the property first. Any excess energy (if any) will be exported back into the grid.
If you consume more than what your solar PV is generating, you will pull energy from the TNB grid as usual.
Example: If your entire family goes on vacation for a long period of time and your usage is less than what you are generating, the excess will be exported back into the grid and is offset on a one to one basis.
i.e, if you export 1 kWh, it will offset against 1 kWh consumed from the grid.
The NEM meter is there to measure the import and export of energy. Here’s what a NEM meter looks like:
Summary
The solar energy system is relatively simple. There are no moving parts to be worried about.