In a white paper on its new string solar inverter, Tesla claims that it is significantly less expensive than competing products from Enphase and SolarEdge.
The company has incorporated more and more into its solar installations over the past few years. Additionally, it supplies it to other solar installers through its certified installer program.
A white paper that Tesla has been disseminating about its solar inverter has now been obtained by Electrek.
Tesla explained in the white paper’s summary:
Tesla’s mission is to accelerate the world’s transition to sustainable energy. To speed up the adoption of solar and storage in the residential energy sector, we’ve focused on providing products specifically designed for both the system owner and the installer. To develop the Tesla Solar Inverter, we leveraged our deep industry experience to design an inverter that offered the best value for system owners, while being easy to install, maintain, and service.
The main claim made by Tesla in the paper is that the Levelized Cost of Energy (LCOE) and the purchase price of its string inverter solution are lower.
Tesla acknowledges in the paper that its solution reduces production by about 1 or 2%:
We then assessed the real-world performance data of these sites to characterize the effects of inverter type on the system’s output. We compared actual system performance data of sites with different inverter types but similar SES, ensuring only similar roofs were compared. For the homes that are good for solar (SES 6-10), sites that used optimizers saw energy production gains of 1-2% compared to homes that used Tesla Solar Inverters. Comparing the cost of Tesla Solar Inverter with MLPEs begged the question of whether the productivity gains were worth the increased cost of the MLAs.
SolarEdge, which Tesla mentions in the white paper and appears to be comparing its solution to in this instance, is the leading manufacturer of optimizers for solar inverters.
They will update if they receive a response from SolarEdge regarding the comparison. The source contacted SolarEdge for a comment.
Tesla claims in the paper that the lower output was worth the trade-off because its analysis yielded a 6% lower Levelized Cost of Energy (LCOE):
To answer this question, an LCOE analysis was performed to compare two 8 kW solar systems4. In the base-case scenario, our analysis found that the Tesla system had a 6% lower LCOE for the most common SES5. We also found that, for 93% of sites in the sample, Tesla had a lower LCOE. The difference in LCOE is driven entirely by higher inverter equipment costs. Further, the gap between LCOEs for SES 8 roofs expands to approximately 15% after factoring in the potential failures of optimizers during the service life6. These findings prove that over the system’s lifetime, the Tesla Solar Inverter will provide energy at a better value for most customers.
Tesla also asserts that its string solar inverter’s ease of installation and site design process solar inverter benefit installers.