Grid-Tied Residential Solar Energy Systems

There has been plenty said about the electricity tariff hike which came into effect this year. I have yet to assess the impact it has on my home’s electricity cost but looking at the cumulative records, it looks quite significant. Thankfully though, electricity cost is no where near what it is in Perth where the bro lives. There, an average household can expect to pay at least AUD1,000.00 ~~per month~~ every two months (billing cycle is two months) in electricity charges. particularly during summer, when it gets so hot, air-conditioning is a necessary evil.

Recently though, the bro had a solar power kit installed at his home which has effectively shrunk his bill by at least 80%! This is made possible because the power generated by the solar panels is fed back into the grid and contributes to the usage. Any excess at the end of the month is bought back by the power company via a rebate on the home owner’s bill.

Just a note from the bro: “We actually use more electricity than the average family here unfortunately so we are on the upper scale for usage. The 1k is also for two months as that’s the billing cycle here. So in essence, for an average household to install what we have, they would be getting paid handsomely by Synergy for all the electricity that’s fed back into the grid.“

The scheme is a government backed one called feed-in-tariff scheme. Feed-in tariffs in Australia have been enacted by several State Governments for electricity generated by solar photovoltaic (PV) systems. Feed-in tariff (FIT) are a premium rate paid to producers of renewable energy. They are a way of subsidising renewable energy and in Australia have been enacted at the State level. In WA, the Feed In Tariff offered by the state government is 40 cents whilst Synergy offers 7 cents via the Renewable Energy Buyback Scheme. Once the customer signs up, they will receive both incentives for the duration of the contract which is 10 years.

I think this is a fantastic idea which we can easily implement here in Brunei Darussalam. It will bring two main benefits, i.e. leveraging on alternative energy sources to ensure energy sustainability, and at the same time reduce the electricity bill. I hope the authorities will seriously consider this scheme, if they haven’t already done so. I for one would definitely sign up!

Solar panels are installed on the rooftop

The inverter

A “grid-tie” solar system is the most common method of installing a residential solar power system. Grid-tie systems are connected to the main power grid and are designed to sell power back to the utility company. In an arrangement known widely as “net metering”, homeowners get paid for the electricity they generate in excess of what they use. This means that a system that produces 115% of a homeowner’s annual electricity needs, the electric utility will pay for the extra 15% that was produced by the system. Homeowners often not only completely eliminate their electric utility bill but they may actually realize a net profit. Net-metering works only on “grid-tie” solar or wind power systems. Because you must be connected to the utility grid, off-grid power systems are not compatible to net-metering programs. These systems can be designed offset any percentage of your kilowatt-hour utility usage.

A grid-tie electrical system is a system that generates electricity and is connected to the main power grid. These systems are typically based on renewable energy sources such as the sun or wind. Solar, or photovoltaic, or PV, grid-tie systems convert sunlight into electric current. Solar panels absorb photons of light from the sun, producing DC current electricity. Another system component, the grid tie inverter, converts this DC current into AC current which can then either be used by electric “loads” in the home or it can be directed onto the main power grid for a credit toward your monthly electric utility usage.

More info here.