Order and Installation: Ordered the system in first week of August 2020. Installed in first week of September (original date was mid-September but an earlier date became available). This is a solar only system with 24 (340 W) panels and 7600 SE inverter.
Design changes: I was able to successfully request changes in the original design. Communication with project coordinator was very good, both through phone and email. Changes involved moving panels from East to West and increasing the number of panels facing South. Final layout has half the panels facing South and remaining half facing West.
No power disconnects during install: Told electrician that kids are attending school from home so he should try to minimize the disruption. He was able to complete work without any power disconnection.
PTO in 4 weeks: It took about 4 weeks from NEM interconnection application (post payment) to PTO. About 2 weeks for application approval and about 2 weeks to swap meter. NV Energy field technician was able to issue PTO email on site after swapping the meter. NV Energy’s expected performance timeline is 10 business days for each step, and they were able to deliver it on last day.
System performance: It has been 3 full months since system became operational. Monthly production so far is in line with NREL estimates (using PVwatts calculator). Tesla annual estimate of 14,200 KWh also matches with NREL estimate. Here are production numbers:
Month (Total production, highest daily, lowest daily)
Oct (1,229 KWh; 44.9KWh; 32.8KWh)
Nov (975 KWh; 37.2KWh; 22.3KWh)
Dec (845 KWh; 33.5KWh; 8.8KWh)
Based on limited data (3 months only), West facing panels are producing about 25% less energy compared to South facing panels. I expect this difference to drop to ~ 20% with annual data but this remains to be seen. I have access to panel level data through SE app (logical layout).
Self-referral reward: About 10 weeks after PTO, I received a $400 check for self-referral. No action was needed on my part to trigger this. 2 weeks before the check arrived, I received an email to confirm my mailing address.
Some (expected) miss-steps: CT’s were incorrectly installed. Field service technician was dispatched to correct this situation (14 days from in-app service request to visit)
Net metering: NV Energy net metering is bit different from most utilities because they use a monthly true-up. Any excess production is converted to credit ($) by using 75% of retail rate (current retail rate $0.1015/ KWh). This credit can only be used to pay for net consumption in subsequent months. It never expires, cannot be refunded to customer, and cannot be used to pay for basic charges. So minimum bill (basic charge) is always $13.17 per month.
Because of local climate (mostly sunny in southern NV), availability of natural gas for heating, and production and consumption patterns, there is typically some excess production from Oct-May and high net consumption during June-Sept (cooling needs). Because of monthly true-up for excess production at 75% of a unit, system must produce about 33% more units during months of excess production to meet all demand on 12-month basis (100 % of past 12-month historic consumption). This is something I overlooked at the time of planning for the system.
Where TESLA can improve:
Design changes: I was able to successfully request changes in the original design. Communication with project coordinator was very good, both through phone and email. Changes involved moving panels from East to West and increasing the number of panels facing South. Final layout has half the panels facing South and remaining half facing West.
No power disconnects during install: Told electrician that kids are attending school from home so he should try to minimize the disruption. He was able to complete work without any power disconnection.
PTO in 4 weeks: It took about 4 weeks from NEM interconnection application (post payment) to PTO. About 2 weeks for application approval and about 2 weeks to swap meter. NV Energy field technician was able to issue PTO email on site after swapping the meter. NV Energy’s expected performance timeline is 10 business days for each step, and they were able to deliver it on last day.
System performance: It has been 3 full months since system became operational. Monthly production so far is in line with NREL estimates (using PVwatts calculator). Tesla annual estimate of 14,200 KWh also matches with NREL estimate. Here are production numbers:
Month (Total production, highest daily, lowest daily)
Oct (1,229 KWh; 44.9KWh; 32.8KWh)
Nov (975 KWh; 37.2KWh; 22.3KWh)
Dec (845 KWh; 33.5KWh; 8.8KWh)
Based on limited data (3 months only), West facing panels are producing about 25% less energy compared to South facing panels. I expect this difference to drop to ~ 20% with annual data but this remains to be seen. I have access to panel level data through SE app (logical layout).
Self-referral reward: About 10 weeks after PTO, I received a $400 check for self-referral. No action was needed on my part to trigger this. 2 weeks before the check arrived, I received an email to confirm my mailing address.
Some (expected) miss-steps: CT’s were incorrectly installed. Field service technician was dispatched to correct this situation (14 days from in-app service request to visit)
Net metering: NV Energy net metering is bit different from most utilities because they use a monthly true-up. Any excess production is converted to credit ($) by using 75% of retail rate (current retail rate $0.1015/ KWh). This credit can only be used to pay for net consumption in subsequent months. It never expires, cannot be refunded to customer, and cannot be used to pay for basic charges. So minimum bill (basic charge) is always $13.17 per month.
Because of local climate (mostly sunny in southern NV), availability of natural gas for heating, and production and consumption patterns, there is typically some excess production from Oct-May and high net consumption during June-Sept (cooling needs). Because of monthly true-up for excess production at 75% of a unit, system must produce about 33% more units during months of excess production to meet all demand on 12-month basis (100 % of past 12-month historic consumption). This is something I overlooked at the time of planning for the system.
Where TESLA can improve:
- Project coordinator should set-up at least one call in the beginning to discuss variations that are not part of a standard project. There are many scenarios, in my case it was load exception due to a recently added EV. This will reduce delays and improve customer experience.
- The workflow for moving panels from ground to 2nd story roof is poorly designed and executed. They attach a hook and rope to panel and a guy standing on roof pulls it up. While moving up, the face of panel is grinding against a metal ladder. With level 2 surface hardness, this leaves scratch marks on panels. They got to do a better job with this.
- There appears to be a need for additional training on installation of CT’s. The avoidable 2nd visit to correct the install increases cost and results in customer dissatisfaction.
- Some TESLA internal systems do not communicate well with each other. I paid my invoice by calling the customer service, instead of using the payment link in the account. The workflow in my TESLA account is still stuck at “Make final payment” stage more than 4 months after payment was made.
