Zero your Electricity Bill - How many home solar panels does it take?

• What is your current electricity consumption?
• How many solar panels are needed to eliminate your electricity bill in your location?
• What energy efficiency could be considered before a solar project?
• How can a building energy consumption and generation be measured in real time?

Suggested Solar Power Home Steps

1. Examine 1 year of electricity bills and see the total kWh used and yearly cost.
2. Consider installing a building energy meter. Work out a baseline for energy used per day.Building Energy Measurement
3. Calculate best suited energy efficiency projects for your situation. Complete projects.Save Energy and Money Checklist
4. See the new efficient baseline energy used per day.
5. Run the Solar Panel Power Calculator

Solar Panel Power Calculator

Parameter	Value
Yearly kWh used	kWh
Your local average daily Solar Radiation World Map Solar Radiation (kWh/m2/day)	kWh/m2/day
Yearly electricity cost (optional)	currency
Press this button after adjusting values above
90% efficiency in the grid inverter or battery charger assumed. Solar Panel Rating using 1 kW / metre square Standard Test Conditions (STC) at 25 oC assumed.
Amorphous Silicon Solar Panels	square metres
or Polycrystalline Silicon Solar Panels	square metres
or Mono crystalline Silicon Solar Panels	square metres
Total solar panel power target STC	watts
Potential 30 year electricity cost savings	currency

Solar Panel Sizes

Home solar panels can come in various sizes and power ratings. See a sample of solar panels below.

Amorphous Silicon Solar Panels	Polycrystalline Silicon Solar Panels	Mono crystalline Silicon Solar Panels
124 watts	190 watts	190 watts
2459 mm long	1571 mm long	1482 mm long
793 mm wide	951 mm wide	992 mm wide
1.95 square metres	1.49 square metres	1.47 square metres

Work out total solar panels area calculator
No. of solar panels
Long mm
Width mm
square metres

Solar Power System Considerations

Grid connected solar power:

Remote connected solar power:

Next step to a free energy home

• Work out the installed cost of your home solar panels.How much does solar power cost?
• Consider the value of free energy for the next 30 years.
• Work out the return on investment using Solar Power Calculator
• Each kWh generated by solar can save approximately 1 kg of CO2 compared to a black coal fired power station.

Home Solar Power Alternatives

Community based solar power systems is a group of citizens combining resources for a larger solar system on a community building, school, above a car park etc.
Advantages include:

• Shared solar installation costs
• Cost efficiencies with larger scale in terms of shared inverter/s, power meter etc.
• Improved change of more ideal solar panel aspect and pitch for maximum energy return
• Project can be independant of you residential location
• Some savings in cooling costs for the building under the solar panels.

Matthewb Homepage	Solar Section	Solar Power Calculator	How much does solar power cost?	Energy Calculators	Building Energy Measurement	Matthewb Site Map