- A standard 300 Watt solar panel produces 300 watt-hours of electricity in a single hour.
- Most solar panels run for 30+ years with no issues and are warrantied for 25+ years.
- In most places in the US a single solar panel will produce about 4 to 6 hours of electricity in a single day. Assuming 4.5 hours of sunshine in an average day, a single 300 Watt panel will produce about (300 x 4.5) 1350 watt-hours of electricity (or 1.35 kWh).
- In other words, to produce the daily consumption of an average US house (30 kWh) that house would need about (30 / 1.35 = ) 22 such 300 Watt solar panels.
- In 2020, standard solar panels cost about $0.50 per watt. In other words, a 300 Watt solar panel would cost about $150 dollars. 22 of them would cost $3300. And they would produce enough electricity to offset an average home’s consumption.
- Unfortunately that price of $0.50 per watt or $3300 for 22 solar panels would not be all the cost. There are also other costs like inverters, racks and mounts, labor costs for design, installation, grid connection, sales costs, etc. which ultimately increase to total system cost to around $1.50 to $3.00 per watt depending on the system size, modifications to existing electric infrastructure in the house, etc.
- So an average solar system size of (300 watt x 22 panels) 6.6 kW and a cost of $2.00 per watt, the cost of an average solar system would be about $13,000 in the US. After tax credit, would cost about $10,000 and would offset about 11,000 kWh of electricity.
- In other words, in an average sunny location, a single household can offset more than 330,000 pounds of coal burning by acquiring a 22 panel solar system (with a cost of around $10,000 in 2020).
- The average cost of electricity (kWh) in the US is about 0.15 cents. In California, it is about $0.20 cents.
- Yet many households pay much higher prices than these due to tiered pricing and time of use pricing schemes.
- In the above scenario, a $10,000 solar system would generate about $2,000 in value each year, assuming an electricity price of 20 cents. A 5 year payback.
Wow that’s great! What about batteries?