You might have heard that solar power plants require significant amounts of land to generate power. How much area indeed is required for solar power plants?
Area required by Solar power plants, be it rooftop or ground mounted is pretty significant. While solar power has some critical sustainability advantages over fossil-based thermal power (coal or natural gas based), one of the key drawbacks of solar is that it recovers energy from a relatively diffuse energy source, sunlight. A 100 MW thermal power plant for instance would require less than 10% of the total area that a 100 MW solar PV power plant would.
Solar power plants require significantly larger land areas compared to conventional power plants. A 100 MW thermal power plant for instance would require less than 10% of the total area that a 100 MW solar PV power plant would.
So how much area is required by solar power plants then?
That depends on the amount of kW of MW you would like to accommodate. A simple rule of thumb is to take 100 sqft for every 1kW of solar panels. Extrapolating this, a 1 MW solar PV power plant should require about 100000 sqft (about 2.5 acres, or 1 hectare).
However, owing to the fact that large ground mounted solar PV farms require space for other accessories, the total land required for a 1 MW of solar PV power plant will be about 4 acres. The above estimate is however for conventional solar PV power plants – those that are based on crystalline silicon and do not use trackers.
A 1 MW of thin film solar plant will require about 30% more area than a similar power plant with crystalline solar modules. So, keep the following in mind as simple thumb rules / benchmarks.
A 1 MW solar PV power plant will require:
4 acres if it uses crystalline solar panels without trackers
6 acres if it uses thin film solar panels without trackers
Questions from the curious cat
While estimating the land area required for solar plants, what factors are to be considered?
The following factors should be considered while estimating the land area required for solar power plants:
- Apart from the panels themselves, area will have to be used up for the control and service rooms for the inverter and monitoring systems.
- Shading of the panels by obstacles in and around can drastically affect the output from it. Hence, the entire area chosen will not be available for power generation. The panels have to be placed after a shading analysis of the region is done in order to minimise the shading effect by any obstacle.
- If trackers are to be employed for the power plants, an additional 1 to 2 acres of land will be required per MW of the plant.
- Additional land area will be required for the storage rooms and workers’ rooms, in the case of solar power plants .This however is usually very insignificant.
Why is the area required (per MW) for a thin film solar panel higher than that for a crystalline panel?
The simple thumb rule is – High efficiency solar panels will require less area for the same MW capacity than lower efficiency panels. Thus, a 1 MW solar power plant with crystalline panels (about 18% efficiency) will require about 4 acres, while the same plant with thin film technology (12% efficiency) will require about 6 acres. The area required by thin film panels is about 50% more than that for the crystalline, as the latter are about 50% more efficient than the former.
If I wish to have solar on my rooftop, can I take my entire roof area for putting up a solar plant?
Most likely not.
Rooftop owners keen on having solar power plants will be well advised to get an estimate of the shade zones on your rooftop – these are the areas in which shades fall for at least parts of the day.
Zones that will have continuous shade should typically not sport solar panels. You hence will need to deduct the shade area when you are estimating the amount of space for a solar power system. In addition, if you plan to place the inverters and the battery systems on the rooftop along with the solar panels, and if you need to construct a separate room for these, you will have to deduct this space as well during your estimates of total possible panel area.
Do solar power plants with trackers require less area than those without trackers?
Solar trackers increase the output of the solar power plants significantly. That is, a 1 MW solar PV power plant with trackers will produce much more electricity in MWh (up to 30% more) than a solar PV power plant without trackers.
Thus, if you were to use energy output as the benchmark, a solar farm with trackers could require less area than a solar farm without trackers for the same output. We say “could,” because the use of trackers necessitate an additional land area for a solar farm.
Solar Mango estimates that an additional 1 or 2 acres is required per MW for a solar power plant which desires to use the tracker technology.
However, in the final analysis, even after taking this additional land requirement, solar farms with trackers are most likely to generate more energy than those without, for a given area.
Is area required for solar power plants a critical factor while setting up a solar power plant?
The cost of land is only a small percentage(less than 5 % of total costs per MW) of the overall costs of a solar power plant. As a result, even if you do not own land, you can purchase land elsewhere and construct a solar power plant. Ownership of land thus provides you with no competitive advantage. The suitability of land with respect to several factors like solar irradiation in the region and others are more important than the quantum of area you already own.
1 kW of solar panels require approximately 100 sqft, or 10 sqm., when used on rooftops and in small ground mounted installations.
Thank you note:
This article had an error earlier in the context of area required while using trackers. Terry Tremwel from Picasolar, Arkansas (USA) was kind enough to point out the error (mid May 2015) and offer the correct explanation, based on which we have corrected the content now. Thank you Terry.