Rooftop solar power can make your property greener by reducing dependence on electricity from the power network, which is produced mostly from coal in Australia. However, you can reduce the environmental footprint of your property even further if you complement solar power with upgrades that reduce electricity consumption, or measures that allow you to manage your energy usage more effectively. Considering the high electricity prices in Australia, all these property upgrades are not only beneficial for the environment, but also for your pocket!
This article will provide an overview of some home upgrades you can consider along with the installation of a solar photovoltaic system. If you are going solar through a Power Purchase Agreement (PPA), the upfront cost is zero and the funds you would have spent on the solar array are freed for other property upgrades.
LED lighting products can be considered cousins of solar panels. Just like a solar panel uses semiconductor materials to turn light into electricity, an LED lamp uses semiconductors to turn electricity into lighting. In addition, both devices can reduce your power bills considerably.
Since LED lighting does not rely on incandescence or gas ignition, it is extremely efficient. You can expect energy savings of over 80% when incandescent lamps are upgraded to LED, and around 40% when fluorescent lamps are upgraded. Also consider that the average LED bulb lasts around 25,000 hours, while incandescents are limited to around 1,000 and fluorescents last between 8,000 and 10,000 hours. You can save many trips to the hardware store over several years simply because lamp replacements become less frequent.
Solar power reduces your electricity bills during the day, while LED lighting does so at night when you depend on artificial lighting. Therefore, both upgrades can complement each other quite well.
The financial benefit of combining solar power and LED lighting is even greater for business clients. Solar panels reduce the heat gain through the rooftop, while LED lights reduce internal heat generation. Combined, these two effects reduce the load on air conditioning equipment. The benefit is even greater if these measures reduce yearly energy consumption below 160,000 kWh, since commercial energy users are spared from the dreaded capacity charge.
Heat pumps are like refrigerators running in reverse: they inject ambient heat into a concealed and insulated space. In addition, they can do it even if the surroundings are cooler through the use of a compressor and refrigerant fluid. Although an electric resistance heater can perform the same function, it only delivers one kWh of heating per kWh of electricity consumed, while heat pumps deliver between 2 and 4 kWh of heat per kWh of electricity (depending on the model and manufacturer).
A heat pump water heater is a great complement for a solar PV system because you can use surplus electricity generation to store hot water. Consider that Australian energy companies only credit surplus electricity fed back to the grid at around one-third of the retail price, so all measures that allow you to consume the full output of a solar PV system are beneficial. This setup allows you to store hot water for later, reducing dependence on both resistance heaters, which are expensive to run; and gas boilers, which produce greenhouse gas emissions.
Consider that heat pumps are eligible for small-scale technology credits (STC), the same financial incentives that reduce the cost of solar PV systems in Australia. This provides an even greater reason to consider a heat pump water heater as a complementary upgrade for a solar photovoltaic system.
Solar power has one key limitation: electricity generation is reduced to zero at night, and drops sharply with cloudy weather. As a result, you cannot count on solar panels to produce electricity 100% of the time. However, this can be solved by adding a battery array. Lithium-ion batteries such as the Tesla Powerwall 2 currently show the most potential, with service lives of a few thousand cycles and the potential for dramatic cost decreases in the short term.
As previously mentioned, feed-in tariffs in Australia remain low in spite of recent increases, so it makes sense to use solar energy instead of exporting it. With batteries, you can store surplus generation from photovoltaic panels to run electrical appliances at night.
Although the price of lithium-ion batteries remains high, it could drop by over 30% before 2020. Solar power was no different a decade ago, but technological development has brought down its price to the point where utility-scale solar farms can now beat the kilowatt-hour price of power plants fired by fossil fuels.
Lithium-ion batteries can achieve synergy with LED lighting during nighttime. Consider that five 60-W incandescent bulbs can consume one kilowatt-hour in slightly over three hours, while five LED bulbs rated at 10W each can operate for 20 hours with one kWh of stored electricity.
Like with any home upgrade, a professional opinion is strongly recommended before upgrading any piece of equipment in your property. You can purchase the most efficient LED lamps or heat pumps in the market, but may still get poor results if they are not adequate for the application at hand. You will want to avoid an oversized heat pump, or LED lamps with the wrong lighting color or beam shape.
If you have the funds and are trying to decide between solar power and energy efficiency upgrades, consider signing a PPA to get solar power at zero upfront cost, while the capital is used to reduce home energy consumption as much as possible.
A general recommendation when purchasing home appliances in Australia is to look for the Energy Rating Label, which ranks products on a scale from 1 to 10 stars, with 10 stars representing top efficiency. As of 2017, the Energy Rating Label program does not cover LED lighting and heat pump water heaters yet, but you can look for the label when purchasing other types of appliances listed in the program website.