EMERALD TECHNICAL TOOL

Solar Yield Calculator

Estimate daily, monthly and annual solar generation, electricity savings and environmental impact from a PV system.

Solar Feasibility Planning

Estimate solar generation and savings before detailed design.

Use this practical planning tool to understand expected PV yield, self-consumption value, CO₂ reduction and simple payback before moving into site-specific design.

PV System Size

kWp

Inverter Capacity

Enter the inverter AC output rating. This helps compare PV array size against inverter capacity.PV Module Wattage

Used to estimate the number of solar panels required.Battery TechnologyBattery Capacity

kWh

Usable Battery Percentage

Usable battery capacity depends on battery chemistry, inverter settings and manufacturer limits.Battery voltage affects DC cable size, DC breaker/fuse ratings, current, losses and inverter compatibility. This calculator estimates energy and backup time using kWh, so battery voltage is not required for the basic yield and runtime estimate.Average Daily Consumption

kWh/day

Use the site's average daily energy usage from the electricity bill or monitoring data.Average Peak Sun HoursCape Town and Western Cape sites often use approximately 4.5 to 5.5 peak sun hours depending on roof orientation, shading and season.Self-Consumption Percentage

Estimated percentage of solar energy used on site rather than exported.Electricity Tariff

R/kWh

System Cost

System Type

Advanced Settings

Advanced assumptions are used for yield, long-term generation and emissions estimates. Most users can leave these as default.

Performance RatioAnnual Degradation

CO₂ Grid Factor

kg/kWh

Estimated Annual Solar Generation

11 844kWh/year

Based on PV size, peak sun hours and selected performance ratio.

Good Design Range

PV array to inverter ratio is within a typical design range.

Daily generation: 32,4 kWh/day
Monthly generation: 973 kWh/month
Annual generation: 11 844 kWh/year
Self-consumed energy per year: 9 475 kWh/year
Estimated annual savings: R 30 319
Estimated simple payback: 4,9 years
Annual CO₂ reduction: 8,5 tonnes/year
25-year generation estimate: 278 985 kWh
25-year savings estimate: R 714 203
Inverter capacity: 8,0 kW
DC/AC ratio: 1,00
DC/AC ratio status: Good Design Range
PV module wattage: 600 W
Estimated number of panels: 14
Estimated roof area required: 33,6 m²
Battery technology: Lithium 48V
Installed battery capacity: 20,0 kWh
Usable battery capacity: 18,0 kWh
Estimated backup time: 10,8 hours
Battery autonomy: 0,45 days
Solar offset percentage: 81%
Grid energy required per day: 14,0 kWh/day

Daily Energy Balance

Solar production compared to site consumption

This compares the estimated daily solar production against the site's average daily energy usage.

Average daily consumption

40,0 kWh/day

Estimated solar production per day

32,4 kWh/day

Self-consumed solar energy per day

26,0 kWh/day

Grid energy required per day

14,0 kWh/day

Solar offset percentage

81%

Emerald Recommended System

PV array size

8,0 kWp

Inverter capacity

8,0 kW

DC/AC ratio

1,00

DC/AC ratio status

Good Design Range

PV module wattage

600 W

Estimated panels

Estimated roof area

33,6 m²

Battery technology

Lithium 48V

Battery storage

20,0 kWh

Usable battery storage

18,0 kWh

Estimated backup time

10,8 hours

Battery autonomy

0,45 days

Estimated daily generation

32,4 kWh/day

Estimated solar offset

81%

Good Design Range

PV array to inverter ratio is within a typical design range.

Balance PV yield, battery storage, inverter capacity and backup circuit requirements.

Roof area is a high-level estimate only and depends on panel dimensions, spacing, access pathways, orientation and mounting method.

Savings Projection

Daily savings

R 83

Monthly savings

R 2 492

Annual savings

R 30 319

25-year savings estimate

R 714 203

Savings are based on self-consumed energy only. Export tariffs, demand charges and tariff escalation are not included in this simple estimate.

Technical Recommendations

Inverter Ratio

Good Design Range: PV array to inverter ratio is within a typical design range.

Battery Storage

Battery backup time is high. Confirm recharge time, project cost and load profile.

Daily Consumption

Solar sizing should be checked against the site load profile. A daytime load profile improves design accuracy and helps avoid oversizing.

System Type

Hybrid systems can improve backup capability and self-consumption, but battery sizing must be matched to load profile and required autonomy.

Solar Yield

Solar yield depends on roof orientation, tilt, shading, inverter sizing, module quality, system losses, maintenance, soiling and local weather conditions. Self-consumption is within a practical range for many commercial solar systems.

Battery Backup Planning

Battery technology: Lithium 48V
Inverter capacity: 8,0 kW
Maximum continuous load estimate: 8,0 kW
Installed battery capacity: 20,0 kWh
Usable battery capacity: 18,0 kWh
Average daily consumption: 40,0 kWh/day
Average load: 1,67 kW
Estimated backup time: 10,8 hours
Battery autonomy: 0,45 days

Battery backup time is based on average daily load only. Actual backup runtime depends on which circuits are connected, peak load, inverter limits and battery manufacturer data.

Maximum continuous load is limited by inverter output rating and manufacturer specifications. Backup runtime depends on the actual loads connected during an outage.

Battery voltage affects DC cable size, DC breaker/fuse ratings, current, losses and inverter compatibility. This calculator estimates energy and backup time using kWh, so battery voltage is not required for the basic yield and runtime estimate.

Professional Solar Design

From Estimate to Detailed Solar Design

This online calculator provides a preliminary estimate only. Before installation, Emerald can complete a professional solar design based on your site, load profile and project requirements.

Online solar estimate

Site inspection and electrical assessment

Load profile review

Roof, shading and installation assessment

PV*SOL energy simulation

Battery autonomy and inverter sizing

Cable, protection and SSEG requirements

Final technical proposal

Installation, commissioning and maintenance

A professional Emerald solar design may include:

Site inspection and electrical assessment
Load profile evaluation
Roof measurements and structural review
Shading assessment
PV*SOL professional energy simulation
Battery autonomy calculations
Cable and protection design
Single-line diagrams
Equipment selection
Financial return analysis
Final technical proposal

Move from high-level estimate to a bankable system design with realistic yield modelling, compliant electrical integration and practical installation planning.

Request Professional Solar Design

Solar Feasibility

Ready for a Professional Solar Design?

Send your solar estimate to Emerald and our team can assist with a site inspection, PV*SOL simulation, battery storage design, SSEG requirements and a detailed technical proposal.

Book a Solar Design Assessment