In the previous article, we explored several aspects that homeowners needed to consider when they plan to set up a solar panel system in their household. The idea of being able to enjoy electricity that you generate on your own is exciting, indeed. You would help to reduce the dependency on fossil fuels while mitigating the effects of climate change. Nevertheless, setting up the system is a serious task. Selection of the suitable equipment, then identifying the system that is suitable for your needs is crucial. You wouldn’t want to discover later that your investment did not yield the outcome that you desired, would you? Read on as we walk you through the requirements for the setup and the choices available in the market.
What Does A Solar-Powered Household Need To Run Efficiently?
The basic set up of a solar panel system consists of three main parts:
1. Solar Panels
The panels are the main component of the system. In most cases, the rooftop has the largest area exposed to sunlight, therefore having the panels on the roof would ensure maximum electricity generation.
Solar panels cost a considerable amount of money to install. To get the most out of your investment, look for these criteria in the product’s brochure:
The efficiency of the panels refers to the percentage of sunlight that gets converted into electricity. A solar panel with 20% efficiency converts 20% of solar irradiation that falls onto the panel into electricity. Current solar panels in the market yield between 15% and 20%.
Solar panels with monocrystalline silicon wafers have higher efficiency as a result of their uniform composition. This type of silicon wafers possesses superior performance in less optimal conditions such as high heat and low light. On the contrary, polycrystalline silicon wafers are less efficient due to their more fragmented composition.
1.2 Degradation Rate
Exposure to ultraviolet radiation and high temperature over time will slowly reduce power output. Although this is unavoidable, some solar panel models degrade slower than their competitors. Compare and choose the one with the lower degradation rate as it would then have a longer lifespan. You may get this information under the performance warranty section.
A panel with a 0.8% degradation rate per year means that by the second year, the panels will operate at 99.2% of their original output. By its 25th year of operation, it will still be operating at 82.5%. Hence, always opt for the model with the lower degradation rate.
The inverters carry an important role where it converts direct current (DC) from the solar panels to alternating current (AC) for general household use. Most electrical appliances run on AC, so without inverters, the system would be nearly useless.
It is important to select an inverter of the correct capacity so that it can run smoothly. The capacity of an inverter is rated in watts (W). Choose an inverter where its capacity is similar to the DC rating of your solar panel system. For example, if you are using a system of 6 kilowatts (kW), the inverter should be around 6kW, plus or minus a small percentage. This is crucial to ensure that the inverters are capable to handle all the power that the panels produce.
3. Electric Meter
The electric meter measures electricity usage for monitoring and billing purposes of each household. The latest version of an electric meter in Malaysia is the Smart Meter. It records your electricity usage and communicates this information automatically to Tenaga Nasional Berhad (TNB) via radio-frequency waves. Not only it helps you to track your energy usage, but it also eliminates the need for a printed paper bill.
However, a household that uses the solar panel system will need two different sets of electric meters:
3.1 Photovoltaic (PV) Meter
Measures and record the energy that the solar panel generates.
3.2 Bi-Directional Meter
Indicates energy usage and excess energy produced.
Choosing A Solar Panel System That Suits Your Needs
In general, there are three types of solar panel systems available in the market:
1. Grid-Tied Solar System
Grid-tied or on-grid is when your system is connected to the utility power grid. It is the most basic and commonly used system. The panels convert sunlight to electricity that the homeowner can use directly.
The initial set-up cost is the lowest among the other available choices. It does not use much equipment nor require tedious maintenance. That would explain its popularity among users.
However, this system relies heavily on the sun’s irradiation. The panel generates electricity only when it receives sunlight. Thus, on a cloudy or rainy day, its efficiency is reduced and the user can’t maximise its benefit. Also, since excess energy flows out to the grid, it needs to be utilised in real-time. The system is incapable of storing energy for later use.
2. Hybrid Solar System
If you prefer to have a system that comes with energy storage, then the hybrid system will suit your needs. It is similar to the grid-tied solar system, but with the addition of a set of battery bank. The battery bank acts as a back-up system when there is a power outage. In case such an incident happens, you can relax as electricity will be drawn from the battery instead of the grid.
If you’re a grid-tied solar system user and wish to upgrade your system to hybrid, you only need to add two more pieces of equipment to your existing setup:
2.1 Solar Charge Controller
Also known as charge regulators, this device limits the rate of current that flows to the battery bank. By doing so, it protects the batteries from overcharging. A good charge controller ensures that the battery can run for a prolonged period.
2.2 Battery Bank
A battery bank, which consists of an array of batteries, stores all the electricity that the panels generate. It is similar to car batteries but can endure repeated charging and discharging in a solar power system. There are several types of batteries you can choose from:
Each battery type has its own advantages and disadvantages. We shall go into further details in future episodes.
Additional equipment would also mean additional costs, which is why this system is not as popular as the grid-tied solar system.
3. Off-Grid Solar System
For those living in secluded areas and cut off from the power grid, the off-grid system is the only choice. The equipment setup is similar to the hybrid system, minus the power supply from the grid. It relies solely on the electricity that the solar panel generates. The batteries store any excess energy that the user can tap later.
This system, unfortunately, comes with its own downside. Not only it is much more expensive to set up, but the user may encounter situations when there is insufficient sunlight. As a result, the panels will not be able to generate enough electricity. For this reason, a backup generator, although optional, is a good investment.
One may argue that increasing the battery bank’s capacity is a better choice. However, batteries are expensive to install and need proper maintenance. They also degrade over time and typically need to be replaced after a few years of use. Generators, on the other hand, can run on diesel, petroleum, and other fuel types. They are also easier to maintain and last longer.
Generating Income From Solar Panels
Homeowners of a grid-tied or a hybrid solar panel system have the advantage of having their monthly electricity bills reduced. This happens when the panels generate more electricity than what was consumed. The excess amount will then be offset from the monthly electricity bill. You may think of it as an income generation scheme, where profits are directly paid to the power provider in return for a lower bill.
This system is known worldwide as Net-Energy Metering (NEM). In Malaysia, it is under the jurisdiction of the Sustainable Energy Development Authority of Malaysia (SEDA). All domestic, commercial and industrial sectors can enjoy this scheme.
To enjoy the benefits of NEM, homeowners would need to request a quota directly from SEDA. Do take note that there is a capacity limit to qualify. For residential units with single-phase wiring, the panel’s maximum limit is 12kW. On the other hand, the maximum limit for units with three-phase wiring is 72kW.
Getting The Advice From Professionals
However, if you appoint a certified contractor to set up your system, then they would be requesting the quota for you. One local contractor that has made a name for themselves in the solar panel installation industry is ERS Energy.
For the past six years, they have completed solar power installations for over 600 homes. With experience in setting up residential, commercial and large-scale systems, ERS Energy can recommend the most suitable system for you based on your monthly electricity consumption.
If you are interested to have a solar panel system installed, you may contact their sales representative at +603 2201 1468 or +603 7972 1468 for more information. Alternatively, you can also send them a message through WhatsApp at +6012 244 8266 or visit their website.
From Luxury To Basic Necessity
Newer solar panels offer higher efficiency, longer lifespan and more cost-efficient than before. The prospect of consistent monthly savings and protection from rising costs of electricity have further fuelled its popularity among residential and commercial users alike.
At the same time, the public is getting more well informed on issues relating to the environment. Realising the negative side effects of continuous dependence on fossil fuels, more and more are switching to renewable energy.
Looking at the current trend, solar panels may soon become a basic household necessity. Who knows, we may see new housing projects pre-installed with solar panels in the near future?