Solar for Strata - Instant Estimates, 'Single Click' Estimates and Solar Feasibility Studies compared

When it comes to moving strata schemes forward on solar, there are different levels of estimates ranging from free estimates to tailored engineering estimates based upon historical metering data. What is the difference....

​Solar installers typically use tools such as Opensolar, Pylon or Helioscope to create sales proposals for strata buildings. However, none of these tools have comprehensive software modules for dealing with solar for apartment buildings. This creates issues with the quality of complex solar for strata sales proposals and has led companies such as Wattblock to offer services such as a Solar Sharing Equitability Review as a pre-installation service.

There are aerial imaging systems such as Nearmap and Metromaps (Aerometrex) which provide high resolution imaging of all the apartment buildings in major metropolitan centres. These are more up to date than google maps, apple maps, sixmaps (NSW government aerial imagery).

AVPI Sunspot Project, Boompower, Ecologic Apps, Allume Energy and Zapcat provide instant estimate online calculators for solar which can be used for strata buildings. 

Wattblock pioneered the 'Single click solar estimates' for a strata scheme on a google map of a local government area. This is an offering that follows a Solar for Strata audit commissioned by a local government area e.g. Canada Bay, North Sydney etc. The aim is to find the right balance between accuracy, usability and simplicity.

Then there are a dozen companies which will give a tailored solar feasibility study for a residential strata scheme. Waverley Council provides a  list of consultants. 

We thought we would unpack the difference between these approaches. The timeframe for a strata scheme to install solar panels is typically 9-18 months as it has to be voted on at an EGM or AGM of all Owners. However, in some cases it has taken up to 10 years from the first solar feasibility study to the actual install to take place. A journey of a thousand miles begins with a single step, which is hopefully a step on solid ground.

Note: For mobile users the table isn't viewable so download the PDF here.

	Instant Solar Estimate for Strata	'Single Click' Solar Estimate for Strata on Google Maps (e.g. Wattblock's Solar for Strata audit)	Solar Feasibility Study
Site Visit	No	No	Yes
Visual Inspection of strata rooftop by qualified solar engineer using up to date  aerial imaging system (e.g. Nearmap, Metromap)	No	Yes	Yes
Historical metering data from common area meter or aggregate metering data from individual lots from electricity monitoring devices	No	No	Yes, if available
Shading Analysis	No	Basic	Advanced
Orientation Analysis	No	No	Advanced e.g. by rooftop zone or by rooftop zone per solar sharing system
Handles different roof pitches for panels within the same solar system e.g. one section flat concrete roof and one section sloped tiled roof on same structure	No	No	Advanced e.g. multiple rooftop zones per solar system or multiple rooftop zones per solar sharing system
Type of strata considered	-Apartment Block ​-Townhouse	-Apartment Block -Townhouse with contiguous roofspace -Townhouse without continguous roofspace	-Apartment Block -Townhouse with contiguous roofspace -Townhouse without continguous roofspace -Converted warehouse -Finger Wharf -Mixed Use -Commercial Strata with range of different commercial tenancies with different load profiles for different tenancies e.g. restaurant, office space
Usable roofspace for solar considered	No	Yes	Yes
Check to see if solar is already installed	No	Yes	Yes
Multiple physical block analysis	No	Yes	Yes
Evaluation of Best Model of Solar to be installed	-Individual -Shared -Common Area	-Individual -Shared -Common Area	-Individual -Shared -Common Area -Shared for apartments and common areas -Multiple Shared Systems for apartments with common area on one Shared System alongside residential lots -Embedded network with solar sharing gateways -Embedded network with billing system solar credits
Solar Analysis	System Size System Cost System Savings ​(after rebates) Payback​	System Size System Cost System Savings ​(after rebates) Payback CO2 emissions reduction	-System Size -System Cost -System Savings (after rebates) -Payback -CO2 emissions reduction ​-Solar Export modelling -Customised time-of-use tariff analysis for common areas in hourly timesteps through 365 days of the year based upon historical metering data from the common area meter -Use of large sample of apartment meter loads for hourly timestep modelling through 365 days as better approximation than grid provider household averages -Customised analysis of individual solar sharing systems where multiple solar sharing systems exist with multiple rooftop areas per solar sharing gateway on different pitches and orientations with potentially different shading effects on different rooftop areas ​- caters for mix of single phase and 3 phase meters at the same site
User Experience	20+ step online navigation	Input address of strata scheme into search bar or ‘single click’ on a google map drop-pin of your own strata scheme to see the estimate	-Request common area bills -Signed authorisation letter for metering data -Site visit including meter audit and number of meterboards -Comprehensive Report -Opportunity for strata committee to ask questions on report -Zoom call to discuss report and questions
Inclusion of Battery Estimates	No	No	Yes. The affect of Battery on Solar System size(s) within usable roofspace constraints i.e. any type of solar system will be larger if a battery is present than if it isn’t present -Battery analysis modelled separately per solar system where there are multiple solar systems -Battery analysis per solar sharing system where there are multiple solar sharing systems -Roundtrip efficiency -Affect of multiple batteries on multiple solar sharing systems sizes within usable roofspace constraints when a separate common area solar/battery system is to be co-located with one or more solar sharing systems
Accuracy	Good for a sustainability champion who is NOT on the strata committee. In worst case scenario will recommend a solar system which is 9 times too large for the available roofspace. Can inaccurately allocate the best type of solar e.g. make a mistake between choosing common area solar and solar sharing as the best option for that property. Can favour one type of solar install e.g. solar sharing	Good enough for the strata committee to allocate funding for further investigation e.g. detailed solar feasibility or solar tender	Reliable enough for a strata committee or Owners Corporation to vote to allocate funding to a solar or solar/battery project
Methodology	Simple estimates e.g. 1.5kW per lot for solar sharing	-12 years of R&D. -Utilises unique datasets supplied to NSW Government for the Apartment Baseline Project -Utilises data supplied to government for the creation of NABERS for Apartment Buildings rating system	Best in Class
Cost	FREE (subsidised by an independent party such as local council)	FREE (subsidised by an independent party such as local council)	$2,000-$6,000 per strata scheme

Additional resources which may assist you on your NSW Solar Banks for strata journey are:

Solar Readiness for Strata online training course here.
40 videos on solar for strata here.
​Find all government rebates and incentives available to NSW strata schemes here.
20 videos of strata committee members talking about electrifying their strata buildings here.
Connect with over 300 strata electrification "champions" on the Electrify Strata Whatsapp community here.