- Dec 18, 2001
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I had been interested in the Tesla Powerwall when it had first come out and got even more interested once the Powerwall 2 version was released with the built-in inverter. In late 2016 I found out about the California SGIP program which provided incentives. http://www.cpuc.ca.gov/sgip/
I looked into the program which historically had mainly been used by Commercial enterprises looking to install larger systems. However with the Tesla Powerwall 2 for battery storage it looked like over 50%+ of my system cost would be covered by a rebate back from the state. Since part of my monthly utility bill went into bucket to pay for this, I kind of figured hell why not. So after some further research I called Tesla. Tesla first claimed to never have heard of the SGIP program, which I explained the program to the sales person she then claimed it only applied to Commercial installs. So I found another company Swell Energy that had knowledge of the program and was willing to fill out all the paperwork the rebate required. So I found myself putting down a $500 deposit to reserve 2 Powerwalls with Swell. The entire episode with Tesla was a bit amusing because later in February of 2017 it was like somebody at Tesla realized that they could use the SGIP rebate to help sell Powerwall systems and they started to work with the program.
It took a while in 2017 for the CPUC to figure out how to handle the large amount of residential customers wanting to use the program to order Home Residential Battery storage. Swell got all thje paperwork filled with the state of CA and a $11k rebate was reserved for me. I then waited a long time for the Powerwall's to get shipped from Tesla but over the last couple of weeks I got the two Powerwall 2's installed and some changes to my house wiring.
[/IMG]
My old breaker box has become essentially just a junction box and all my circuits are now wired into the box on the left which has completely replaced my old main panel. The panel in the center is the Tesla Gateway which manages the power flow and is also a ATS (Automatic Transfer Switch) for the system. The panel on the far right is the new generation panel. The batteries and my PV system are wired into this box. In the event of grid power loss the battery system can acts as a whole house backup and the Solar System will continue to charge the batteries if the sun is out. Normally PV inverters go offline in the event of loss of power to the grid. However the Tesla gateway tricks the inverters into thinking grid power is still online and they will continue to supply power. The two Tesla Powerwall's are mounted side by side and have a total of 27 kwh of storage.
However the main usage of the system is for power shifting for the TOU rate plan. I can charge the batteries in the morning when the Sun is peaking and then use the batteries into the afternoon-evening while the grid demand is at the highest to minimize my electrical draw during these peak times. During the summer months SCE (Sothern California Edison) for TOU, the rate is 48 cents kwh from 2pm-8pm. From 10pm-8am it is only 12 cents kwh. So only a daily basis the Powerwall units will allow me to very effectively time shift my electrical usage from the grid to the cheaper parts of the day.
Here is a snap shot of my electrical usage yesterday.
The blue parts represents the electrical usage for my residence. The first one is when the oven came on to cook dinner. You can then clearly see on the far right the second spike when my car charger came online later in the evening. The EV charger has a time of use function built into the charger. I have the charger to setup to only charge between 11pm-7am. This allows me to plug the car in but it will not start charging until 11pm.
The yellow part is solar generation.
The green represents battery usage. So below the baseline represents the charging of the battery system which was completed around noon. Then as the PV production goes down you can see the battery usage increase and you can see to large peaks. The first one is when the oven came on to cook dinner. The larger spike later in the evening is from EV charger starting, draws about 6 kw's (27A x 220v). I have the battery system set to reserve about 40% in-case of power failure so the batteries don't get drawn all the way down. I am still playing around with this setting a bit.
The grey represents grid pull and push. You can see the load early in the morning and then as solar production increases it completely takes overall the house load and then the excess power charges the battery. As the battery is charged to 100% then the excess power is feed back into the grid.
A recent code update from Tesla makes available TOU settings but my system hasn't received it yet. This is supposed to better optimize the system to take into account TOU.
[/IMG]
[/IMG]
I looked into the program which historically had mainly been used by Commercial enterprises looking to install larger systems. However with the Tesla Powerwall 2 for battery storage it looked like over 50%+ of my system cost would be covered by a rebate back from the state. Since part of my monthly utility bill went into bucket to pay for this, I kind of figured hell why not. So after some further research I called Tesla. Tesla first claimed to never have heard of the SGIP program, which I explained the program to the sales person she then claimed it only applied to Commercial installs. So I found another company Swell Energy that had knowledge of the program and was willing to fill out all the paperwork the rebate required. So I found myself putting down a $500 deposit to reserve 2 Powerwalls with Swell. The entire episode with Tesla was a bit amusing because later in February of 2017 it was like somebody at Tesla realized that they could use the SGIP rebate to help sell Powerwall systems and they started to work with the program.
It took a while in 2017 for the CPUC to figure out how to handle the large amount of residential customers wanting to use the program to order Home Residential Battery storage. Swell got all thje paperwork filled with the state of CA and a $11k rebate was reserved for me. I then waited a long time for the Powerwall's to get shipped from Tesla but over the last couple of weeks I got the two Powerwall 2's installed and some changes to my house wiring.
My old breaker box has become essentially just a junction box and all my circuits are now wired into the box on the left which has completely replaced my old main panel. The panel in the center is the Tesla Gateway which manages the power flow and is also a ATS (Automatic Transfer Switch) for the system. The panel on the far right is the new generation panel. The batteries and my PV system are wired into this box. In the event of grid power loss the battery system can acts as a whole house backup and the Solar System will continue to charge the batteries if the sun is out. Normally PV inverters go offline in the event of loss of power to the grid. However the Tesla gateway tricks the inverters into thinking grid power is still online and they will continue to supply power. The two Tesla Powerwall's are mounted side by side and have a total of 27 kwh of storage.
However the main usage of the system is for power shifting for the TOU rate plan. I can charge the batteries in the morning when the Sun is peaking and then use the batteries into the afternoon-evening while the grid demand is at the highest to minimize my electrical draw during these peak times. During the summer months SCE (Sothern California Edison) for TOU, the rate is 48 cents kwh from 2pm-8pm. From 10pm-8am it is only 12 cents kwh. So only a daily basis the Powerwall units will allow me to very effectively time shift my electrical usage from the grid to the cheaper parts of the day.
Here is a snap shot of my electrical usage yesterday.
The blue parts represents the electrical usage for my residence. The first one is when the oven came on to cook dinner. You can then clearly see on the far right the second spike when my car charger came online later in the evening. The EV charger has a time of use function built into the charger. I have the charger to setup to only charge between 11pm-7am. This allows me to plug the car in but it will not start charging until 11pm.
The yellow part is solar generation.
The green represents battery usage. So below the baseline represents the charging of the battery system which was completed around noon. Then as the PV production goes down you can see the battery usage increase and you can see to large peaks. The first one is when the oven came on to cook dinner. The larger spike later in the evening is from EV charger starting, draws about 6 kw's (27A x 220v). I have the battery system set to reserve about 40% in-case of power failure so the batteries don't get drawn all the way down. I am still playing around with this setting a bit.
The grey represents grid pull and push. You can see the load early in the morning and then as solar production increases it completely takes overall the house load and then the excess power charges the battery. As the battery is charged to 100% then the excess power is feed back into the grid.
A recent code update from Tesla makes available TOU settings but my system hasn't received it yet. This is supposed to better optimize the system to take into account TOU.
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