SUNBIZ

Solar Home System

Solar power or solar cells might sound strange or some­thing from the future but it’s quite a commonplace. As more global discoveries are be­ing made about the benefits of hav­ing
20 Oct 2018 10:32
Solar Home System
The Solar Panel kit is becoming more popular among consumers, because they are convenient.

Solar power or solar cells might sound strange or some­thing from the future but it’s quite a commonplace.

As more global discoveries are be­ing made about the benefits of hav­ing solar power, more businesses and households are investing in this area.

You might have a solar-powered watch on your wrist or even solar-powered lights in your garden.

We know that some materials pro­duce electricity when exposed to light, though it was not until the mid-1950s that the solar cell was first manufactured and demon­strated.

Solar photovoltaic (PV) was used in the 1960s mainly for powering space vehicles such as the space rover and satellites since it was too expensive for general use.

By the 1970s the cost of PV had fallen enough to be used for remote power for telecommunications and water pumping.

The cost of solar cells has dropped continuously since the 80’s, when a watt of solar panel cost around FJ$21.

Today the wholesale price of pan­els costs about FJ$6 – FJ$8 per watt of panel power.

In developing countries, rural and village solar electrification projects have seen many homes electrified with solar power.

International Energy Association (IEA) estimates that 70,000 panels are installed every hour world­wide.

In Fiji, we have about 40 compa­nies installing solar systems with an estimated thousand workers in this trade sector.

It is estimated that more than 10,000 solar home systems (SHS) have been installed Fiji wide, and this number continues to grow.

Factors to consider before investing in solar power

When considering whether to in­vest in solar power, one should con­sider the following:

  • Cost of the solar equipment
  • On or off grid connected systems
  • Characteristics of your home roof
  • Installation costs
  • Long term plan and return of in­vestment

One needs to take time to shop around to get the best price for quality equipment you need for your installation.

Since Fiji is in the southern hemi­sphere, your installation costs should be cheaper if your roof faces north, and the frames to face the panels in the right direction, should also be an affordable range.

Solar home system components consist of the solar panels, a bat­tery bank, a charge controller and an inverter.

The solar panels supply energy to the load and for charging the bat­tery bank.

The batteries store the electri­cal energy from the panels to discharge them when the load de­mand is more than the panels can produce.

The charge controller ensures that the battery bank is not over­charged or over discharged.

This helps prolong the life of the battery bank.

The inverter converts the direct current (DC) from the batteries to alternating current (AC) at 50Hz (hertz), 240V (volts), the same as our local utility supply.

The inverter is the central compo­nent that binds the whole system together, therefore, high reliability is paramount (High reliability is —If the equipment that is installed or maintained is not steadfast the probability of failure is high) as it is the component most likely to fail other than the batteries.

Inverters types are as follows:

  • Off-grid and grid-tie inverters
  • Pure-sine and modified-sine wave inverters
  • Low-frequency and high-frequen­cy inverters
  • MPPT (Maximum power point tracker) and PWM (Pulse width modulation) charge inverters.

Getting trained with NTPC

If installation or labour costs are high, you can consider getting trained with the National Training & Productivity Centre so that you can install and maintain your sys­tem. Interested persons can under­take the ‘Solar PV Principles and Applications’ course, which offers hands-on training on:

  • designing the solar home system depending on the location and load requirements,
  • installing and testing the solar home system,
  • maintaining the system compo­nents so you can get the best return on investment, and
  • Troubleshooting the system faults and rectify them.

Our training mode is 30% theory and 70% practical where the cap­stone assessment is the installa­tion of a solar home system.

NTPC has been providing this so­lar training course since 2008 and we have conducted an average of nine courses per year with a total of 83 courses to-date.

This skills set training is popular with tradespeople who work for so­lar system installation companies. Due to the increasing demand over time, our programmes are con­ducted at our Narere, Lautoka and Labasa centres.

Challenges with solar power

Since our training participants are from the workforce, one of the biggest challenges they highlight­ed in the field is resizing a system to suit the load requirements.

Precaution must be taken at all times when under-sizing the sys­tem as this will shorten the life span of the inverter and battery bank. Over-sizing the system will have additional costs. Should the components load increase, there needs to be a balance to allow for flexibility that is affordable to ones pocket during installation. A larg­er solar home system is not always better for the home owner.

Lack of maintenance is a major factor that causes a solar system installation to malfunction. Many solar homeowners carry out an inspection when the system be­comes faulty or when it system stops working. This should not be the practice. Solar systems re­quire constant routine inspection to identify potential faults in order for it to be rectified

A properly maintained solar home system can last for 10 years or more. Solar home systems that are not maintained properly usu­ally fail in five years or less.

Other sources of renewable energy

Due to the changing weather pat­terns in Fiji, the solar system alone may not be the ideal solution for electricity generation.

We can tap into developing other renewable technologies such as wind turbines, thermoelectric generators (TEG), mini-hydro tur­bines, and fossil fuel generators to be used only as a back-up power system. Firewood can be used to produce electricity with the ther­moelectric generator (Thermo­electric materials generate power directly from heat by converting temperature differences into elec­tric voltage).

In rural communities and villag­es, it is possible to work together to in install a hybrid of these renewa­ble technologies to generate power into local settings.

The NTPC, while conducting training in solar and fossil fuel power generation, is also under­taking research and designing short courses for wind power, mi­cro-hydro systems and thermoelec­tric generators.

This is expected to substantiate in the coming years as we work to­wards generating electricity using renewable resources.

Solar power has grown over the years and is at the forefront of power generation.

Solar systems can help contribute to a pristine and sustainable Fiji environment, for a better future for our country and our children.

Feedback: maraia.vula@fijisun.com.fj

Subscribe-to-Newspaper