PPA are growing in popularity now because of the growth of the renewable’s industry, and PPA's have been signed for periods up to 20 year.
At Wikipedia they describe a "Power Purchase Agreement (PPA), as a contract between Two parties, one which Generates electricity (the seller) and one which is looking to Purchase electricity (the buyer).
The key point here is that PPA's are not leases. This is because customers are buying electricity, not a solar system. The benefit here is that unlike with a lease, the expense of the solar system does not appear on the customer's balance sheet, which can be helpful for businesses.
It's a lot like a traditional electricity provider - except that here, providers are investing in a new energy generation system, so a commitment to buy the electricity is usually part of the deal.
There are a number of variations on the PPA theme - here's a summary of the ones most relevant to solar electricity.
Large scale renewable production like wind farms and solar farms are very expensive. Companies building them need to be sure demand will be strong and revenues will flow. So they offer large electricity buyers (usually businesses) agreements at very attractive prices.
This way they lock in customers and a price that will be profitable. These have grown in popularity in Europe and the US in recent years, and in Australia we are puling more our weight.
Behind the meter PPA's
DAT & common fixed panel Rooftop Solar Array electricity has the advantage of generating energy right where it is being consumed, where DAT Racking generates Peak energy for double the hours of Fixed Panels !
PPAs that focus on solar generation are called "behind the meter" PPAs, because the electricity flows directly into a site, behind the point at which grid based electricity is connected to the meter.
The major advantage of this system is that you don't have to pay network charges, which suposadly make up 35% - 50% of grid-based electricity, proven to be less than half that inflated cost.
These PPAs are well suited for businesses, schools, and other organisations who love the idea of going solar and paying less for electricity, but don't want to pay anything upfront, and don't want to have to monitor or maintain the system.
Businesses also like them because it's a lot less work than buying a solar system. No need to research providers and work with installers. No need to get a loan.
Because the sun doesn't shine all the time, many businesses will stay connected to the grid. So they feel comfortable knowing they will always have power, but they get the benefit of using cheaper solar power for much of the day.
Within this group of PPAs, there are a number of variables - here are some important ones.
1. Ownership transfer
At the end of the PPA agreement, some providers will transfer ownership of the solar system to the building owner. This can be a good deal because panels generally come with 25 year warranties, so at the end of a 10 year agreement, you'll have 15 more years to enjoy 'free' solar energy. You may need to replace inverters which have shorter warranties, but it's often not a bad deal.
2. Pay for what you use
Some PPAs are production based - the customer pays for all the energy produced whether they use it or not. Others offer a consumption based agreements - pay only for what you use.
3. Fixed price
Some PPAs will increase the price per kWh over the life of the agreement to allow for inflation. Some offer a fixed price that will not change for the term of the agreement. Some customers prefer a longer agreement to ensure this price is locked in lower (and is lower).
And here are a few of the ways Upstream Energy's PPAs are a bit different.
Each system based on the unique requirements of each customer. This ensures installing the right number of panels with the right tilting to deliver the energy they need, and obviously more to require a PPA .
It also means tailoring the agreement - for example it can range from 10 years to 25 years or more. As mentioned, sometimes longer agreements are attractive because the price per kWh is generally lower, it's locked in for longer, and because some customers would prefer to have us maintain the solar systems for as long as possible.
If you are renting the Land or Building, a 10 year agreement might be a problem. We understand.
Commonly renting customers commit to just 12 months PPA. After 12 months they're free to move out if they need to. That is needed to be sure the panels stay put, even if you don't.
You will need to ask the owner of the land or building for permission to keep the panels in place for 10 years. Luckily, they're usually happy with this since they'll be getting a free solar at the end of the agreement with over 10 years warranty on the panels (and Renters usually don't Consuming large amounts of energy from a large system anyway).
Monitoring & maintenance
With each installation, we include a smart meter which helps with faster billing, and also with alerts for dips in power delivery. If an alert comes up you may not know it, but we'll see it and schedule maintenance to fix it.