Development and advisory. Across the life of a solar PV plant.

The map reads by columns, from the first phase to the last, and by rows, one lane per party: Altheon, the delivery partners, the project owner and the providers of capital.

In Altheon's lane a line runs across the four phases. It is solid, with filled nodes, in phases 1 and 2, where Altheon carries out the work; it is dashed, with hollow nodes, in phases 3 and 4, where Altheon coordinates work done by partners. At each phase a thread drops from the line to the node in the delivery partners' lane.

The table gives, phase by phase and lane by lane, the same information as the drawing.

The drawing puts the producer on the left and the buyer on the right. Between them, from the top: the contract, which sets price, term and volume profile; electricity, with a solid line through the grid; guarantees of origin, with a dotted line starting from the GSE. Below, GME's PPA Bulletin Board and the contract variants.

• The contract. In EU law a renewables PPA is a contract under which a natural or legal person agrees to purchase renewable electricity directly from a producer (Directive (EU) 2018/2001, art. 2, point 17).
• Electricity. In a physical PPA the electricity is delivered to the buyer; in a virtual, or financial, PPA the traded electricity is not physically delivered. In an on-site PPA the plant is directly connected to the consumption site, behind the meter (study for the European Commission, DG ENER, 2026).
• Guarantees of origin. They are electronic documents whose sole function is to prove to a final customer that a share or quantity of energy was produced from renewable sources (Directive (EU) 2018/2001, art. 2, point 12). In Italy they are issued by the GSE, are worth 1 MWh each and are traded on GME's M-GO market or bilaterally (GME, Glossary). The directive requires Member States to ensure that guarantees of origin can be transferred to the buyer (art. 15(8)).
• The profile. Under pay-as-produced the buyer pays only for the electricity actually generated, as measured by the plant's meter, and bears the shape risk and much of the volume risk. Under baseload the buyer pays for a fixed volume over a set period, and the difference from actual output is borne by the producer (DG ENER study, 2026).
• The PPA Bulletin Board. Article 28 of Legislative Decree 199/2021 tasks GME with an electronic bulletin board to bring together parties interested in long-term renewable electricity contracts, with an obligation to register contract data. It has been operational since 26 April 2022 and has three sections: anonymous, non-binding announcements, registration of concluded PPAs by sellers, and Energy Release (GME).