Solar panels continued
This presentation is the property of its rightful owner.
Sponsored Links
1 / 13

Solar Panels Continued … PowerPoint PPT Presentation


  • 107 Views
  • Uploaded on
  • Presentation posted in: General

Solar Panels Continued …. George Skarbek 9 th July 2014. Why purchase Solar Panels?. There are a number of reasons Help the environment Cut the power bill Eventually reach a payback period Receive a better return on your investment than you can get elsewhere

Download Presentation

Solar Panels Continued …

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Solar panels continued

Solar PanelsContinued …

George Skarbek

9th July 2014


Why purchase solar panels

Why purchase Solar Panels?

There are a number of reasons

  • Help the environment

  • Cut the power bill

  • Eventually reach a payback period

  • Receive a better return on your investment than you can get elsewhere

  • Or probably several of the above reasons


Reducing the power bill

Reducing the power bill

  • Reducing the power bill is probably one of the main reasons to install solar panels

  • However, you can reduce your power bill just by making some alterations to your house and life style without adding any solar panels

  • Some ways are:

    • Replace incandescent globes with energy efficient globes such LEDs

    • Prevent draughts

    • Turn down the thermostat a bit in winter (put on a jumper) or turn it up in summer when cooling


What pv size should you install

What PV size should you install?

  • This is probably the hardest question to answer

  • You can ask for advice or obtain from your electricity provider 12 months of half hourly generation data and spend days trying to work it out based on the average solar generation in Melbourne by months. However, even then you may not get it quite correct but you will be close.

  • Optimum orientation is facing North. Facing due East or due West you will lose about 14% of energy. East is slightly preferable.

  • Avoid shade as this has a HUGE effect unless you have micro inverters on the panels. See: http://www.aussiemadesolar.com/micro-inverters-explained/ for Tinda panels.


Payback period

Payback period

  • This is asked very often but the installers tend to give quite optimistic estimates as they want your business

  • The Feed In Tariff (FIT) is 8 cents/kWh

  • Percentage of energy exported is the single most important factor in determining the payback period

  • In Melbourne, if exporting 10% of your generation the payback period is 6 years, exporting 50% it is 9 years and exporting 90% it is 24 years (Business spectator) This assumes that the price of electricity will not change over this period.

  • A high regular load, such as a pool pump, will reduce the payback period


Vested interests in payback calculations

Vested interests in payback calculations?


Return on investment roi

Return On Investment (ROI)

  • A better way of looking at the economics is to use ROI first and then the payback period. I will illustrate with our example. Our solar 2 kW installation cost $2,800 and was installed in July 2013. The eight panels had to face due West.

  • The money in Macquarie bank was earning 2.5% therefore interest lost was $72 pa.

  • In the last 12 months solar energy generated = 1,825 kWh

  • Solar energy Exported was 850 kWh @ 8 c/kWh or $68 rebate

  • Solar energy provided 975 kWh saving in energy @ 25c / kWh = $244

  • Therefore the nett saving is $312 giving a ROI of 7.7%


Oversizing the pv array

Oversizing the PV array

  • The inverter is the single most expensive component.

  • However, as PV panels have come down in price, by adding more panels than the inverter’s capacity it is possible to gain additional energy for a small additional cost. Say, install 2.5 kW of panels and a 2 kW inverter.

  • When the solar generation exceeds the capacity of the inverter, it will just go into a less efficient mode, without any damage, in most cases.

  • Check with your installer and with their recommended inverter before oversizing. Do not oversize above 50%.


Oversizing the pv array1

Oversizing the PV array


Who to get for your installation

Who to get for your installation

  • Start by obtaining at least three quotes.

  • If you have a very old switchboard in your house (over 40+ years old) then you may need a switchboard upgrade. This will cost $600+ on top of the installation cost, if required. Send in photos if nobody inspects your house.

  • A good starting point is this site: http://www.solarquotes.com.au/installers/

  • There you can obtain three quotes and then look at the reviews of the installers.


Generation profile on a sunny march day

Generation profile on a sunny March day

This is for a 5 kW system


March usage for our 2 kw system

March usage for our 2 kW system


Solar panels continued

Any Questions?


  • Login