Yield modelling is especially important to a PPA structure. When UrbanVolt funds the system, the yield model feeds directly into the PPA tariff, the client’s savings case, and the performance baseline for the full contract term. The process is designed to move quickly on well-designed projects, and to give both parties confidence in the numbers before a spade goes in the ground.
For background on how UrbanVolt’s EPC partnership model works, start with How Solar EPCs Unlock Funded Pipeline with a PPA.
P50, P90, and what the portal handles for you
Most commercial solar yield reports are produced on a P50 basis – the median expected annual yield. UrbanVolt’s PPA tariff is calculated from P90, the conservative case the system is expected to meet or exceed in nine years out of ten.
In practice, this doesn’t change anything in the EPC’s workflow. Submit your P50 figure through the Partner Portal and UrbanVolt derives the P90 in the background. The EPC produces what they would produce for any project; the conversion happens automatically. A well-constructed P50 produces a P90 that translates directly into a PPA rate that the client can rely on from the initial estimate onwards.
Tool-agnostic, methodology-led
UrbanVolt doesn’t mandate a specific modelling tool – the review is focused on methodology rather than software. What matters is that the model uses an appropriate irradiance dataset for the site and accounts for loss factors.
Where our assessment identifies a meaningful variance with the EPC’s model, your dedicated account manager will work through it collaboratively to reach a position both parties have confidence in.
In most cases, this is a process that confirms the design rather than questions it.
What makes a model straightforward to review
The inputs that most affect review speed are irradiance dataset selection, near shading methodology, and system loss assumptions. Models built on equipment specifications and survey data tend to clear quickly and produce tariff outcomes that reflect the genuine quality of the design.
EPCs who specify Tier 1 equipment – as UrbanVolt requires across all projects – benefit from an optimal and accurate yield. The performance characteristics of premium panels and inverters, applied accurately in the model, produce a yield figure that holds up across the contract term and supports a stronger financial case than a model built on mid-market equipment assumptions.
In summary
Yield modelling in a PPA project is the same discipline EPCs apply on any commercial installation – applied carefully, with good data, to a design built on quality equipment. The difference is that UrbanVolt views the yield not only from a generation perspective, but from an investment perspective too. The outcome is a smooth process and accurate proposals from the start.
Interested in partnering with UrbanVolt? Take a look at our partner page, or contact us to talk through the process.