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of the renewable energy sources (RES) were
deployed utilizing this framework, whereby
licenses were auctioned to produce a specific
quantity of energy in return for a predetermined
tariff per megawatt-hour (MWh).
On-site PPA
Rather than selling all excess energy back to the
grid,
particularly
from
energy-intensive
activities such as running company servers, they
aim to increase the proportion of RES in their
overall energy mix. They can achieve this by
obtaining power directly from a generator and
entering into a separate PPA to either sell the
excess power produced or serve as a backup
supplier if needed.
Sleeved off-site PPAs
In a Sleeved PPA, the corporate consumer sells
all the power it generates to a licensed supplier,
sometimes known as a balancing party. This
arrangement is like a Back-to-Back PPA, where
the electricity supplier purchases all the power
acquired by the consumer. The consumer
repurchases the electricity it consumes to
accomplish the balancing function.
Synthetic PPA
A Synthetic PPA, also referred to as a "Virtual
PPA," is a contractual arrangement in which a
power generator obtains the market price for
their electricity under the PPA, and the generator
and consumer reconcile the difference between
the market price and a predetermined fixed
price. The virtual nature of electricity purchases
in most Contract for Difference is due to the
absence of physical acquisition of electricity.
As illustrated in Table 1, various business models involving Power Purchase Agreements (PPAs)
exist to facilitate energy transactions. These include the Wholesale PPA, where the energy generator
sells all produced power back to the grid at predetermined tariffs, and the On-site PPA, where
companies seek to increase their renewable energy mix by obtaining power directly from a generator.
The Sleeved off-site PPA involves selling generated power to a licensed supplier, while
the Synthetic PPA focuses on reconciling the difference between the market and agreed-upon prices,
often referred to as a 'Virtual PPA.' Each model caters to different business needs and operational
structures in the energy market, enhancing both flexibility and market adaptability [10].
2.2 Virtual PPAs (vPPAs)
A VPPA is a multi-year bilateral renewable energy contract (It usually lasts about 8-20 years) sourced
from a specific plant. Because of the structure of a VPPA, such deals are also known as “contracts
for differences,” or “fixed-for-floating swaps,” since the buyer is effectively paying a fixed $/MWh
rate and receiving a floating market $/MWh rate in return. It is only available in regions with a