At the time of writing, work is being undertaken by a local Committee to seek consultation with residents and Governments as to what is the preferred system that could supply Daintree Coast residents with grid power. This committee was asked by the previous State Government to undertake this consultation. A number of landholders would be willing to connect into a clustered grid system, subject to conditions and cost, while others are satisfied with their current system. Most agree that with a grid system there does need to be consideration given to feed power generated from each home or business back into the grid.
There are various options for power generation under the current scenario, including solar, hydro, batteries and generators, and most people use a combination of these. Unfortunately, solar panels are least efficient in the wet season when power consumption is highest, so most systems here consist of solar panels and a generator to produce the power, and batteries to store it. It is the lucky few who have access to hydropower. Even if you have had experience with solar panels in a grid-serviced area, there is a lot you still need to know about Remote Area Power Systems (RAPS), sometimes called Stand Alone Power Systems (SAPS). Another misconception is that once you have made the investment you won’t have to pay for power anymore. After paying for generator fuel, generator and battery maintenance, and eventual replacement of batteries, panels and inverter, you will probably find you pay significantly more for your power than if you were on the grid. Technology is changing constantly and setting up a RAPS is a big undertaking, even if for someone who’s done it before, so take your time and do your homework. Here are some general tips to get you started.
It is recommended you engage a system designer and installer. The first rule of thumb with all contractors here is they need to have local experience. Ask how long and how often they do work north of the river and ask for local references.
An installer that also provides maintenance will have a better idea of on-going performance of their product, and a supplier that doesn’t install will have less idea.
Expect a design consultation from your installer – if they don’t offer one, find someone that does.
A good designer will:
+ look at your power usage and load and recommend ways to minimise them,
+ advise on sun paths and solar windows,
+ probably lower your expectations,
+ not recommend you buy an off the shelf system – the conditions here are too unique.
Incorrect use and maintenance will damage your system and can be dangerous. If you have a system installed by the previous owners of your property it is strongly recommended that you contact the installer (the phone number should be somewhere on the equipment) and arrange an inspection and driving lesson. If there’s no phone number, find an experienced local contractor.
Many systems include a degree of automation and self-assessment – key readings can be downloaded and emailed to your supplier, who will identify and diagnose issues remotely. Generally automation is not recommended in the tropics, due to vulnerability of electronic controls. Most RAPS however are designed for use on boats and rugged areas, and professionals advise the good quality automated systems are designed robustly enough to withstand it here.
The Alternative Technology Association (ATA) is a not-for-profit organisation that conducts research and provides expert, independent advice on sustainable solutions for the home to households and industry. They have a great website and forum for energy and water related topics, including RAPS, available to everyone. For $50 a year you can also get expert advice, access to their on-line library and a subscription to ReNew or Sanctuary. There is a Cairns branch that organises local events and sends out a monthly newsletter to members.
Have a read of this fact sheet on setting up a RAPS, by the NSW Government.
There is a bigger market in off-grid systems in the yachting industry, and there are parallels in the types of environmental stress components will be exposed to, so look for ideas there.
No matter the system you choose, it will be expensive and require some expertise and maintenance, so you should first look at how you can use less energy around the house.
Purchase energy efficient products and consider the capacity of your system and the length of time they will be used. You may find you have to turn the news off to boil the water in an electric kettle.
Install LED lighting. LED technology continues to develop at a rapid pace.
- Consider gas appliances over electric, particularly the fridge and stove.
- Turn off and unplug at the wall any appliance not being used so as to reduce the demand from standby power.
- Keep seals on fridges and freezers clean and replace them as soon as necessary, especially during the wet season. A gas fridge is more expensive, but will significantly reduce the amount of power you need to generate, and may mean you don’t need power at night or when you go away.
- If you need constant power, for example for a composting toilet or wastewater plant, you will need batteries.
- A smaller dwelling will generally be more efficient, so try to maximise use of space before extending.
- Air-conditioners will probably use more power than all your other needs combined, so try to keep your house cool through good design and insulation instead.
- Watch your input/output readings when different appliances are switched on, or when you try new power saving techniques to find your best power saving options.
Have a look at the Alternative Technology Association’s list of energy saving tips for more.
Most systems here include solar panels, but that doesn’t mean they are ideal although technology improvements in solar panels is moving at a rapid pace.
- They require a certain amount of cleared land to allow sunlight in, and regular removal of overhanging branches that block light. Maximise the use of cleared space with strategic placement of panels and consider pruning trees rather than clearing them altogether. If you do need to clear, leave as much undergrowth as possible to retain biodiversity.
- They require cleaning at least every 6 months – of fallen leaves, mould, and gecko and rat excrement.
This is a high lightning strike area – it’s a good idea to get surge diverters or some form of lightning protection. This will protect your panels and power system as well as you appliances and computers.
Hydro power is a good complement to solar power, as it will perform during the wet season when solar production is at its lowest, and it is cheap and reliable. If on your property there exists a year running creek that has a good fall, this could be the most efficient way of generating power.
Not many people here have use hydropower but do try to track down those that do, for advice.
If you are on a hill, wind power may be an option for you, and although the technology has benefitted from significant development around the world in recent years, there are few or no households using it here, so you will be a bit of a pioneer. As with all options, assess the suitability of the equipment for the climate and minimise clearing by choosing an already cleared site close to the house. The higher up your turbines are the less likely they will be hampered by regenerating rainforest in the future.
The most important thing to know is that wet-cell batteries can be dangerous and need careful storage and maintenance. Your system designer will advise on the best place to store them, and your installer on maintenance. You can also arrange a maintenance contract with some installers.
sDo a daily checking of battery acids to measure their charge and regular change-over of batteries and replacement and disposal of old non-functioning batteries.
AGM (Adsorbed Glass Mat), or gel-cell batteries are fully ,sealed and combined with smarter inverters and chargers, are safer and require less maintenance than older-style flooded or wet cell batteries.
- Lithium batteries are considered new technology, but definitely need to maintain close attention to this technology.
Most systems rely on a back-up generator – but they come in many shapes and sizes, so be clear about what you need prior to choosing.
A petrol generator is cheaper to purchase than a diesel generator, but a diesel will have a much longer life and is generally cheaper and quieter to run and release less carbon monoxide.
Petrol and diesel generators require regular filling of fuel tanks which in turn requires movement of fuel from storage areas – be mindful of spills and health and safety. Position the generator shed and storage area in close proximity, away from drainage lines and at least 30m from creeks to minimise this.
- Transporting fuel by road is dangerous – drive with extreme caution.
- Storing large amounts of fuel is dangerous – try to limit the amount you store and store it away from the house.
Gas is generally safer to use and transport, and emits less carbon monoxide, so you can safely house your gas generator closer to the house and minimise additional clearing.
Choose a generator appropriate to expected demand. Generators are very inefficient if under-loaded. Therefore, have high amp appliances such as washing machine, clothes drier, welder, etc ready for use when the generator starts.
They require regular maintenance depending of the make, model and usage. Ask around who can undertake this maintenance if your not so inclined/skilled
If your generator or fuel storage area won’t fit in the cleared area around the house, restrict clearing to the under-story, even if it’s a regrowth area – the forest canopy is home to many threatened species and takes a lot longer to regenerate.
Components of a power system
Current regulator + lightning protection + inverter + charger
- This is a high lightning strike area – it’s a good idea to get surge diverters or some form of lightning protection. This will protect your power system as well as you appliances and computers.
Your power can be used directly as DC power, or converted into 240V AC power by an inverter. It is more efficient to use the power directly as DC, but more convenient to use AC from the inverter – you can use a mixture of both. Your choice will have an impact on your house wiring and choice of appliances, and vice versa.
Some inverters are more efficient than others, and the quality of the system may be more about the quality of the inverter than the power generator (solar panels, etc).
You will also need a charger to charge your batteries.
An inverter charger is exactly what the name suggests – it does the job of both the inverter and the charger. It can be more efficient and less expensive, but is used more widely in the marine environment than the domestic.
Wasps and geckos will move into the fans and vents – clean them regularly and keep them insect-proofed if possible.
Maintenance of a power system varies significantly depending on your components, but you will most likely need to:
- clean solar panels at least every six months
- transport fuel regularly
- get regular generator and battery services (regularity depends on the specific product)
- check battery acids
- replace batteries every 7-10 years, depending on maintenance, storage and technology of your batteries, and
- clean vents and fans of wasp nests and geckos.