INFORMATION

Do you need an ALTERNATIVE to MAINS Electricity ?

ECO SOLAR ENERGY is a company that specialises in designing, supplying and installing Solar Powered electricity systems to homes and community buildings. We also install grid connect, wind and micro-hydro systems where appropriate. Eco Solar Energy has BCSE (Business Council for Sustainable Energy) full accreditation and membership No.FDI576. We are also accredited for the QLD REDRS and PVRP rebate schemes.

The above systems all attract a rebate available from Qld Government EPA (Environmental Protection Agency)

TO FIND OUT IF YOU ARE ELIGIBLE FOR A REBATE VISIT     www.epa.qld.gov.au/sustainable_energy

If you have not yet built a house, some thought might be given to designing it with energy efficiency in mind.

A building that is designed to reduce your dependence on heating in winter and air conditioning in summer not only costs less to run, but will also reduce the energy resources you require. Orientate your house/building TRUE NORTH with a roof line facing EAST WEST with no more than a 30 degree pitch where sun is available from 7am - 5pm daily or longer.

Hot water is necessary for comfortable living. Solar hot water systems can provide much of your requirement from a free resource.

Use the most appropriate power source for each application eg. Wood or gas for cooking, heating and boosting hot water.

An interesting  fact is that most renewable energy sources are Solar.

	Direct solar radiation is used for solar photovoltaic electricity and also water heating.
	Wind power - heating & cooling of the Earth’s surface causes wind flows.
	Hydro power - the sun evaporates water to form clouds.

Stand-Alone power supply systems using renewable energy will usually require some sort of auxiliary power generation facility eg. Generators. Those who already rely on diesel/petrol/gas generators can improve the reliability and reduce fuel/maintenance costs by updating to a Battery - Inverter system, with a percentage of renewable input.

Where ‘mains electricity’ is available you can have a grid-connected renewable energy system installed to provide surplus energy to the electricity mains and take some back when you need it.

By using the most energy efficient appliances available you can significantly lower the amount of energy and the capital cost of the power system you require.

ECO SOLAR ENERGY uses Australian Standards guidelines to ensure you of a safe and reliable solar electricity system.

BE AWARE THAT A CHEAP SYSTEM IS OFTEN THE ONE THAT COSTS THE MOST IN THE LONG RUN

ECO SOLAR WILL DESIGN, SUPPLY & INSTALL A QUALITY, EFFICIENT, RELIABLE RENEWABLE ENERGY SYSTEM AT AN AFFORDABLE COST FOR LONG LIFE OUTPUT.

 

WHERE DO I START ?

Electricity is a high grade energy because it can be easily converted to other forms, such as ...

Heat    -    Using an electric element     or

Mechanical energy    -    Using an electric motor

It is suitable for a wide range of tasks, but in renewable energy systems the capital cost of electricity production is high. One of the main factors governing the cost of providing a stand-alone power supply is deciding which appliances should be powered by electricity. This is often a life style and economic decision.

Both ‘power’ and ‘energy’ are terms that have been used in the preceding paragraph.

We need to define them:        

Power (watts) is the rate in which energy is produced or consumed

Energy (watt-hours) equals power multiplied by time (hours) E = P x t

The most important part for determining the size of any electric power system is the energy requirement.

Using electricity to change the temperature of a space is the most energy intensive (and hence highest cost)

The most appropriate energy source should be selected for each task, such as ...

Cooking

LPG is often the most appropriate for stoves and ovens, but this does not mean that electric jugs, frypans and microwave cookers are off the list if they are used infrequently or for short periods. Wood stoves are also useful.

Water Heating

Solar water heating is the preferred option with instant heat LPG or wood(combustion stove) backup.

Space Heating

An energy efficient house design is the best option to reduce heating energy needs but again the energy requirement to heat large areas is best left to wood or gas heaters.

Dishwashers

Automatic dishwashers with electric water heaters will use a large amount of energy to heat the water. An alternative is instant LPG heating for this task. This means that the dishwasher electric heating can be replaced with LPG heating but an exemption for this modification must be sought from the Qld Dept Health.

Clothes dryers

In some tropical areas, during the ‘wet’ season, clothes dryers are necessary. Thought should be given to using a heat source other than electricity for this purpose. In most areas the sun & wind do a good job for free, also a good sized reliable generator can be used.

Refrigeration

Gas (LPG) fridges can be used to reduce the initial power system cost but they are quite expensive units and readily availability of LPG is necessary. Where LPG is used for cooking it may not be a problem to provide the extra. The remaining option is to use the most energy efficient electric refrigerators suitable for your home, 12V & 24V DC and modern 240V AC low energy fridges are available.

Space Cooling

Energy efficient house design with sufficient ventilation (with fans, if necessary) is the best option. Air conditioning with electric motor compressors use large amounts of electrical energy. In the right climate evaporative air conditioning may be a lower energy use choice.

 

LOAD ASSESSMENT WORKSHEETS

In a stand-alone power supply, electricity can be provided to the dwelling in two forms -

dc direct from the battery bank.

ac (240V) from an Inverter (converts DC from the battery to AC) or from an engine driven alternator.

Some appliances can be powered direct from the battery bank, such as dc lighting, dc energy efficient refrigeration and dc pumps. (In many cases the use of dc appliances is minimised.)

Modern inverters are used to power standard ac appliances because of the lower cost and better availability of 240V AC equipment.

To enable ECO SOLAR ENERGY to provide the best solution for you, it is necessary for you to provide an estimate of your daily energy requirement. This is most easily done by using a daily electrical load assessment worksheet. The process involves listing all electrical appliances that will be used.

Alongside each appliance in the list it is necessary to note the power rating and an estimate of the time in minutes or hours per day that each appliance is used. The usage time is often the one that takes a bit of thought.

If you would like a copy of a LOAD ASSESSMENT WORKSHEET click the link, highlight the table and copy the table to MS Word, you can then fill the form out and email it to us. Alternatively you can print the page, fill it out and post it to us.

From there we can design and calculate the size system you require.      

It is in your own interest to select the most energy efficient appliances that will fulfil your needs

All appliances should have the power rating (in W or VA) written on them or on an attached plate.

Some 240V ac appliances, such as pumps, will also give a maximum current rating. Others such as washing machines, clothes dryers, air conditioners and refrigerator will have an energy rating label as well.

For example ...

A 5 star energy rated refrigerator may have a comparative energy consumption of 500 kWh/year. The energy consumption figure is measured at a temperature of 20ºC. The run time of the refrigerator will vary greatly depending on the ambient temperature and thus the energy consumption will change.

Standard fluorescent lighting is 9 to 36 watts per tube, but because we live by the clock and not the sun, the usage time will be greater in winter than summer.

Electric motors starting under load require a large amount of power to get them running. This is sometimes noted on the attached ratings plate. The manufacturer often needs to be consulted to determine start up surge and continuous power ratings. Eco Solar Electrical can assist you with determining power usage and energy efficient appliances.

 

WHAT DO I NEED TO PROVIDE?

 

Wind and micro-hydro generators are very site specific and will often require extensive resource measurement to enable accurate prediction of future energy production. Solar (photovoltaic) power systems are not so site dependant and future energy prediction is simpler, using past, long term, average solar radiation and temperature data from different regions of Australia.

Regardless of the renewable energy source, it is necessary to provide a suitable equipment and battery enclosure. At least 2.5m2 of floor space is required for a typical domestic battery & equipment area. This area must provide sufficient ventilation for the battery bank and the electronic equipment. Also some separation between the battery bank and the electrical equipment (regulator, Inverter etc) is required. A cool environment is essential for maximum life of batteries and electrical equipment. This area must be secure (lockable) and should be vermin-proof. Eco Solar will help you with enclosure details.

Suitable resources and sites are required for wind and micro-hydro generators.

Solar modules require a North facing aspect, free of shade from trees or other obstructions, installation of Solar modules can be on roofs or ground mounted arrays.

 

GENERATORS

The majority of RAPS Solar/Wind powered electricity systems require a back up Generator/Battery charger.

The Hours run time of Generator/Battery Charger required per day or week, is determined by the shortfall of Ampere Hours (AH) charging in the Batteries by Solar/Wind systems.

The Generator/Battery Charger comes into use when long patterns of overcast weather reduces input from Solar/Wind to battery bank. A battery bank normally has a 5 no sun days reserve in the design.

Wet cell lead acid Batteries require an equalization charge once every 1-2 months to ensure gassing which reduces sulphation of plates, therefore prolonging Battery life. A Generator is used when high power appliances such as welders, compressors, clothes drier etc. are needed which generally are not suitable to use on an Inverter.

Solar/Wind powered systems can be designed with a generator supplementing power required per day or week. This reduces the number of Solar Modules required for overcast or winter days.

A correctly designed system based on your daily load assessment worksheet incorporating sufficient solar modules and a large battery bank can supply the majority of power required, thus reducing generator run time. It is possible to design a system without a Generator/Battery Charger which incorporates a large number of solar modules and a large battery bank of gel cell batteries (which do not require an equalization charge) and a large inverter. These systems can be expensive but can totally run by Solar/Wind Power.

Four Types of Generators are Available.

A) PETROL - These units are rated for around 1000 hours use, then require a service                          overhaul.

B) DIESEL - These units are rated for 10,000 hours use then require a service overhaul.

C) GAS FIRED GENERATORS - Efficient, Long life, Good performance but more                                                              expensive than diesel units.

D) DIRECT DC GENERATORS - Good efficiency for charging batteries but generally no                                                              240V Available off the same unit.

A Solar/Wind system with back up diesel remote start generator means that the inverter/controller can be used to automatically start and stop the generator when top up power is required in Battery Bank on shortfall days due to extra usage or overcast weather patterns.

Whilst it is possible to have a Solar/Wind powered system that does not require a back up generator making the cost of the system high, it can be seen that a generator does play an important part in charging and maintaining a reliable home power system.

It is recommended that a minimal size of 6 kVA generator be purchased for the operation of a battery charger and back up power for RAPS systems.

Send mail to ecosolar@sun.big.net.au with questions or comments about this web site.
Last modified: April 03, 2003 Website Created by Ecosolar.