The solar industry has seen rapid growth over the past decade, and a major contributing factor has been the surge in solar farms popping up across the globe. In this article, we’ll explain the different types of solar farms, how much they cost and how to start one.
What is a solar farm?
A solar farm, sometimes referred to as a photovoltaic power station, is typically a large solar array supplying electricity to the power grid. Many of these massive arrays are owned by utilities and are another asset for the utility to supply power to properties in their coverage area.
A broader definition of solar farms could include other ground-mounted solar arrays large enough to supply power for many households. This general concept of a solar farm could be associated with both residential community solar and larger utility-scale solar.
Types of solar farms: utility-scale and community solar
There are two main types of solar farms around the country: utility-scale solar farms and community solar farms. The main difference between the two is their customers, as utility-scale solar farms sell directly to utilities, while community solar farms sell directly to end-consumers of electricity, such as homeowners and renters.
Utility-scale solar farms
A utility-scale solar farm (often referred to as simply a solar power plant) is a large solar farm owned by a utility that sends electricity to the grid. Depending on the installation’s geographic location, the power produced at these farms is either sold to wholesale utility buyers through a power purchase agreement (PPA) or owned directly by an electric utility company. Regardless of the exact structure, the original customer of the solar power is a utility, who then distributes the generated electricity to residential, commercial, and industrial customers connected to the grid.
Community solar farms
The idea of community solar has taken off in recent years as more homeowners have realized that they can go solar without putting solar panels on their own physical roof. A community solar farm—sometimes referred to as a “solar garden” or roofless solar —is a farm whose electricity is shared by more than one household. In most cases, a community solar array is a large ground mount installation that spans one or many acres.
Visually, these solar gardens resemble utility-scale solar farms, but they are often smaller in size. Customers can either purchase a share of a solar garden and own that portion of the overall array or they can lease energy from the solar system and, in a sense, replace their monthly utility payments with monthly community solar payments that are typically at a lower price. You can find community solar projects in your town or state in our Community Solar Marketplace.
How much do solar farms cost to build and install?
Solar farms at the utility-scale will typically be at least 1 megawatt (MW), which is a power plant capable of supplying some 200 households. Though cost will range based on a number of factors like location and available sunlight hours, top commercial provider First Solar has stated that the cost per watt for solar installations at this scale is somewhere around $1/watt. Therefore, you can assume that a 1 MW solar farm would cost roughly $1 million to install.
If that value sounds unusually low in comparison to typical costs associated with residential solar ($2 to $4 dollars per watt), it should. The “economies of scale” concept is in full effect with the solar industry.
What is the largest solar farm in the world?
The largest solar system installed in the world is the Pavagada Solar Park, which was fully completed in 2019 in India. The 2,050 MW array can supply energy to hundreds of thousands of households.
It should be clarified that these massive solar plants are more commonly referred to as “solar farms” than smaller ground mount arrays often see with community solar projects. Solar systems at the scale of the Pavagada Solar Park are the size of entire towns and thus take on the name “solar farm” to reference the size of the install (see above image). The term more commonly used with community solar is “solar gardens” due to the fact that the system could be only a few acres and could even live in someone’s backyard.
Rooftop solar vs. solar farms
Joining a community solar farm can be a great option if your roof isn’t right for solar or don’t want solar panels installed on your property. Even if your roof is good for solar, enrolling in a community solar project can still be worth it if the costs are low and the contract terms are beneficial. As community solar projects become more common and the contract terms become more consumer-friendly, solar farm options will compete even more with rooftop solar. However, each individual property has unique challenges and considerations, and there’s no easy way to determine if you’re the right candidate for joining a solar farm.
Check out our comparison of rooftop and community solar for a more in-depth look at how the two options stack up against one another.
Building a solar farm: how does it work?
When developers are considering building a solar farm, whether it be a 50 kW array or a 50 MW project and larger, here are five key questions they’ll ask:
1. How many acres do I need for this size of a power plant?
A smaller solar farm may only require a few acres of land whereas a large utility-scale solar farm can require hundreds of acres (for reference, the above mentioned Kamuthi Power Plant spans 2,500 acres).
2. How will electrical connection work?
You’ll need to consider the location of the land and whether or not it’s situated close enough to power lines and electrical panels to feasibly connect your array to the power grid or to a centralized power source.
3. How will I clean and maintain the plant?
Whether or not the location has water sources or cleaning options will be important in order to maintain the efficiency of so many solar panels that are situated so close to the ground. The Kamuthi Power Plant, for example, is constantly cleaned by a team of solar-powered robots.
4. How many solar panels will I need?
In order to make sure you’ll be able to meet the expected energy demand with your solar farm, you’ll need to first start with the needed kilowatt hours of energy and work backward to get a number of panels you’ll need for the array. To calculate this figure, you’ll need to determine the solar panel production ratio for your area to understand how much energy a certain solar panel wattage will provide. Check out our full explanation on how to do this type of calculation.
5. What’s a good price for my solar installation?
For larger arrays, there will likely be significant discrepancies between quotes from various contractors, so it will be important to get a few bids from different companies. Solar Power World compiles a list of top solar developers each year that can be a helpful starting point.
If you’re in the early stages of considering a residential solar installation, rather than a solar farm, our Solar Calculator can offer a free estimate for what the array might cost, when you could break even on the investment and how much it could save you over time. For those interested in the community solar options in their state, check out our network of Community Solar Providers.