Commercial Solar Assessments
Enhar's commercial solar PV feasibility assessments are conducted by our solar PV experts and provide independent advice on the optimum solar PV system capacity commensurate with your site's electricity consumption, roof and electrical constraints.
Solar Resource Assessment
We conduct a detailed solar resource assessment by obtaining solar resource information from multiple solar insolation datasets local to the site under consideration. The solar resource assessment is specific to the roof and/or PV panel orientation proposed.
The solar data produced includes average hourly insolation data and average daily insolation data for each month in the calendar year. Both fixed tilt and tracking solar PV arrays can be accommodated.
Electricity Bill analysis
A review of the most recent 12 months of electricity bills is conducted to assess the site specific peak and off peak tariff structures along with the associated amount and variation of peak and off-peak electrical demand over the year.
If available, smart meter interval data over the course of the most recent 12 months is used to generate average hourly load profiles for a typical weekday, Saturday and Sunday for each month. Alternatively the load profile of the site will be estimated based on discussions with the client and typical times of electrical consumption.
Accurate hourly consumption data is essential to determine the ratio of site-consumed to grid-exported solar electricity. This information forms the basis of a solar installation's financial case.
Solar Roof and structural assessment
Through a site visit and analysis of satellite imagery a detailed assessment of the roof will be conducted to identify obstacles, roof type and orientations. Optimum and appropriate roof areas for the installation of solar PV arrays will be identified and recommended.
Enhar have a relationship with an experienced structural engineer who can conduct a detailed solar PV structural assessment of the roof/building structure to confirm the suitability of the proposed solar installation.
As part of the assessment Enhar will recommend appropriate mounting options (i.e. pitched, flush mounted or tracking arrays) specific to your site and building type based on the general recommendations made by our structural engineer associate.
Enhar have extensive experience in solar PV shading analysis on difficult roof spaces. Using a combination of software developed in house and three-dimensional sketching software we produce detailed scaled drawings of hourly shade lengths and paths to assist solar array design and layouts. Identification of shade obstacles can be performed by a desktop study using online satellite imagery or an on-site inspection.
The shading profile between 9am and 3pm at the winter solstice is provided for each obstacle to identify roof areas where solar PV should not be considered. Where shading on the panel array between 9am and 3pm is unavoidable a detailed output loss calculation can be conducted.
Solar PV output calculations
The average hourly and daily solar outputs per month are calculated for a solar PV system using in-house spreadsheet software which can be correlated with PVsyst software. The solar output is based on:
- The solar resource data specific to the site and proposed PV orientation
- Technical data from the solar PV panel and inverter specifications
- Estimated system loses due to panel temperatures over the year based on the power temperature coefficient and NOCT of the panel, local BoM temperature data and roof type
- Overall system percentage losses such as DC/AC wiring losses and soiling.
Detailed average solar hourly output analysis is conducted for the proposed PV system and overlayed with the average hourly electrical load profile. This allows a detailed calculation of the tariffs that apply during the hours of solar PV generation over the course of an average year.
This analysis allows the generated solar power to be accurately allocated into the amount of peak tariff electricity consumption avoided, off-peak tariff electricity consumption avoided and electricity exported to the grid where solar generated power exceeds demand.
This analysis is critical in conducting an accurate financial assessment of the installation and determining the optimum system size that avoids the export of generated solar electricity to the grid at a feed in tariff rates much lower than the saving made by off-setting retail electricity rates.
Optimum solar PV sizing
Detailed modelling is conducted to provide an appropriate and optimum solar PV system size with consideration of:
- Available roof area, site constrains and local shading lengths/losses
- Hourly electrical load profile, PV output maximises offset of peak load while minimising export to the grid.
- Maximising the financial return to the end client
- Grid connection constraints
Solar Financial Assessment and modelling
A commercial solar assessment includes a detailed financial assessment and modelling of the costs and revenues of the recommended installation over its projected design life. The analysis includes:
- Calculated solar PV outputs per year including annual output degradation based on warrantee information
- Calculated annual savings due to avoided tariffs (peak and off peak) and annual income via the sale of exported electricity at the available feed in tariff rate.
- Percentage annual increases in electricity prices
- Annual maintenance costs
- Tax depreciation benefits and
- Renewable energy certificate revenue (LGC/STC)
The output of the financial assessment includes:
- a graphed financial projection of the installation over its 25 year design life
- simple financial payback
- Internal rate of return
- Net present value
- A detailed financial spreadsheet displaying itemised expenses and incomes over the installation's 25 year design life.