There are many types of solar electricity supply available. The two most popular methods are a standalone Rooftop Solar installation on your own home, where you generate and supply your own power. The other option is to connect to a larger solar farm.
Solar farms generate low-cost democratized energy. A rooftop solar installation only supplies one property. Solar farms are a cheaper electricity source than rooftop solar installations. The downside is Solar farms can negatively ruin the countryside landscape.
When deciding to install a rooftop solar system or purchase energy from a solar farm, you will need to consider the following pros and cons.
Quick Comparison Of Rooftop Solar and Solar Farms
The primary differences between Rooftop Solar and Solar Farms are.
|Rooftop Solar||Solar Farms|
|Significant Upfront Investment By Consumer||No Upfront Investment By Consumer|
|Long Term Cost 20 Cents Per Kilowatt Hour||Long Term Cost 4 Cents Per Kilowatt Hour|
|No Recurring Costs||Monthly Cost|
|Zero Emission Power Supply||Zero Emission Power Supply|
|No Extra Land Usage||Considerable Land Usage|
|No Impact on Landscape||Significant Aesthetic Impact on Landscape|
|Battery Backup for Low Sun Conditions||No Battery Backup for Low Sun Conditions|
|Maintenance and repair costs are for the owner’s account||No Maintenance or repair costs for the user|
|Not dependant on the national grid. No supply interruption.||If the national grid fails, there will be a supply interruption.|
To decide which option would suit you better, you first need to understand what is meant by rooftop solar and solar farms.
What Is Rooftop Solar?
Rooftop solar is an installation of solar capturing devices placed on private houses or businesses. These devices only generate enough power for the occupant’s needs.
Any surplus generated energy is usually sent to a battery and consumed when the weather is poor or at night-time, when the sun’s energy is not available. Rooftop solar installations are rarely used for income generation, as the available power is insufficient.
What Are Solar Farms?
Solar Farms are large installations of Solar Voltaic Panels that absorb the sun’s energy and convert it to electricity.
A solar farm typically sends its energy to the national electricity grid or subscribing users in a specific community. Users sign a power purchase agreement with the solar farm, which commits them to purchase an agreed amount of electricity units over a particular period.
There are two categories of Solar Farms, which are.
- Community Sized Farms
- Utility Sized Solar Farms
What Are Community-Sized Farms?
Community-sized farms are small-scale solar installations that generate around 5 Megawatts of Electricity for a local community.
The community pays for the installation costs, and the community members share the power. If the facility is not sufficiently sized, there may not be enough energy for all recipients to go completely off-grid, and they may still have to draw part of their electricity needs from the primary grid.
Despite this, participating in a community grid should ultimately reduce users’ electricity costs.
How Do Utility-Sized Farms Compare?
Utility Sized Farms are extensive installations covering large land expanses and generating massive energy of up to 750 megawatts.
One of the largest utility-sized solar farms globally is the Kamuthi facility which is in Tamil Nadu in India. This power station covers 10 square kilometers and consists of 2.5 million individual solar panels.
The plant generates 748 Megawatts capacity and can power 150,000 homes.
Utility-sized solar farm installations are viable alternatives to fossil-based renewable electricity power plants. Already the Kamuthi installation generates 15% of the output compared to one of the Medupi Power stations in South Africa, which is one of the top five coal-fired power stations in the world; it produces 4,800-megawatt (MW)
The Solar site generates its power with zero damage to the atmosphere. It was built and commissioned in 8 months, compared to a 14-year build time for Medupi.
A utility Sized Farm typically sends its energy to the national electricity grid. The electrical utility distributes the electricity as part of its network.
For the sake of brevity, the following comparison between the rooftop system and solar farms will use the Utility Sized Solar Farm model as the point of reference.
How Do Rooftop Systems and Solar Farms Compare?
Solar energy is a zero-emission source of power. Once installed, irrespective of the type of facility, you will have done your part to ease the strain on the environment.
So, do you choose a rooftop system or sign a power supply agreement with a solar farm?
What are the pros and cons of each system?
What Are The Pros And Cons Of Solar Farms?
Commercial Solar farms are proving to be an increasingly viable replacement for old technology power stations.
Solar Farms Offer Many Advantages
- Solar farms require no upfront capital investment. The investors incur the cost of creating the solar farm in that facility. With large-scale utility-sized installations, the investors are the company that owns it. With Community Sized installations, this is usually the community themselves.
- Solar Farms make this zero-emission power supply accessible to all participating homeowners.
- Lazard’s Levelized Cost of Energy calculates the lifetime cost of a private home’s roof-mounted system at 20¢a kilowatt-hour against 4¢ a kilowatt-hour for utility-scale solar energy, delivered through the national networks.
- Solar farms are virtually maintenance-free. In the unlikely event that the farm experiences a fault or suffers damage, the repair cost is for the account of the solar farm and not the individual user.
Disadvantages Of A Utility-Scale Solar Farm
- Utility Sized Solar Farms take up a large amount of space. The Kamuthi solar farm In India (described earlier in this article) uses 10 square km of land and consists of 2.5 million solar panels.
- Using up so much space may result in unacceptable changes to the landscape.
- In unsuitable solar conditions, solar farms may produce less power than needed.
- Solar Farms are dependent on the national grid. If this fails, there will be a supply interruption.
What Are Rooftop Installations Pros And Cons?
Rooftop installations are attracting vast levels of investment due to their many advantages and few drawbacks. The advantage and disadvantages are:
The Advantages Of Rooftop Solar
- Once the initial purchase and installation costs are spent, there are no further ongoing expenses.
- If the sun conditions are not perfect, the battery still supplies power.
- The homeowner retains flexibility in choosing the designed output of the system.
- A rooftop solar installation requires no additional land usage, and therefore the Rooftop solar system has the same footprint as the homeowner’s building.
- Rooftop solar systems have no impact on the aesthetics of the landscape.
- Rooftop systems are not dependent on the national grid, so there is minimal chance of a supply interruption.
The Disadvantages Of Rooftop Solar
- Rooftop solar systems are expensive. The homeowner bears this cost; this may put a rooftop solar system out of reach of many homeowners.
- Amortising the cost of installing the rooftop solar system over the long term makes the rooftop solar system’s cost five times more than sourcing electricity than a utility-sized solar farm.
- The homeowner bears any maintenance or repair costs.
Rooftop solar and Solar Farm installations use the same technology and offer similar atmospheric environmental benefits. Each one has its benefits, and as a result, each will appeal to different types of consumers.