appreciate your response. the following is not practical: install power in a residential house on a per appliance or per end user type of plan ? use microinverters / batteries and install as close as can to the end user or appliance. get one doe move to the next. Group the ones where it makes sense. as you can tell i am a newbie..... this concept at least sounds nice....may not be practical.....haha
grid tie inverter recomendations
- Thread starter lordulrich
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zanydroid
Solar Wizard
Why would you do it that way?
There is a hack to tie microinverters to big appliances and turn them only if those appliances turn on. This is a simple steampunk way to achieve zero export solar.
I don’t have a huge objection to this… except you could get permits and an interconnection agreement with minimal net metering benefits. It’s not that expensive or hard to learn how to do code compliant, permittable microinverter install.
Having random expensive LFP batteries sitting around all over the place would be kind of wasteful and probably more dangerous than you want. It’s also actively counter to what residential fire code has been trying to do about battery placement.
There is a hack to tie microinverters to big appliances and turn them only if those appliances turn on. This is a simple steampunk way to achieve zero export solar.
I don’t have a huge objection to this… except you could get permits and an interconnection agreement with minimal net metering benefits. It’s not that expensive or hard to learn how to do code compliant, permittable microinverter install.
Having random expensive LFP batteries sitting around all over the place would be kind of wasteful and probably more dangerous than you want. It’s also actively counter to what residential fire code has been trying to do about battery placement.
Ok, i am trying to get started and develop a basic design that would work for my situation. Ultimately I would like to power a 3500 sq ft house that has: 4,800 watt HVAC, 2 fridges, it has nat. gas for heater unit in the attic, electric stove, as the main power consumers, the rest are lights and tvs. I would like to learn as I go, but at least get the fundamental / basic design right. I am looking at the eg4 6000 xp hybrid inverter and getting used solar panels, not sure about batteries yet, they seem so expensive. I live in texas and electricity is around .11 / kwh.
How to learn the lower and upper limits of this system so I don't buy the wrong solar panels or some other mistake.
and i do not want to place the panels on the roof, it would need to be someting in the yard or on a wall of a brick house.
Appreciate a few tips.
Thanks
How to learn the lower and upper limits of this system so I don't buy the wrong solar panels or some other mistake.
and i do not want to place the panels on the roof, it would need to be someting in the yard or on a wall of a brick house.
Appreciate a few tips.
Thanks
Hedges
I See Electromagnetic Fields!
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$0.11/kWh is relatively low. I don't think you can beat that with an off-grid battery and PV system.
If you have net metering, I think you can make a grid-tie PV system with between $0.50 and $1.25/W worth of hardware, producing power for $0.01 to $0.03/kWh (amortized over 20 years.)
Find out about net metering options. There may be some half-way system that will reduce cost, making some of your power. Or, for a premium price, you can have battery backup during failures.
What I did is grid-backup, with a battery only big enough for the night. During the day, most of the power for A/C etc. doesn't go through batteries.
If you have net metering, I think you can make a grid-tie PV system with between $0.50 and $1.25/W worth of hardware, producing power for $0.01 to $0.03/kWh (amortized over 20 years.)
Find out about net metering options. There may be some half-way system that will reduce cost, making some of your power. Or, for a premium price, you can have battery backup during failures.
What I did is grid-backup, with a battery only big enough for the night. During the day, most of the power for A/C etc. doesn't go through batteries.
To make sense on the cost, it seems the system needs to spend more on the solar panels that anything else if possible and find a way to use the power when the sun is out and not use the grid. So the savings would really only be when the sun is out. Is there a way to minimize the costs of a hybrid inverter ? Would it make sense the eg4 6000xp and solar panels with small or no battery ? what would be a few options ?
zanydroid
Solar Wizard
There are inverters that work in battery less mode. You might as well also consider grid tie inverters (non hybrid).
I think net metering plans are balkanized in Texas so you have to dig into your individual situations.
I think you will want to play around with PVwatts to see what kind of generation is possible with your location in the summer. Maybe you can take the edge off your AC. And then for winter production, maybe you can save some minor bucks as a bonus.
BTW wall (vertical) is going to be terrible in the summer. And mounting on wall/ground is going to be costly/complicated compared to roof mounting. Roof mounting has the greatest economy of scale in parts and in permit-ready processes (IE getting people to draw plans for you, for low cost equipment). Fundamental cost angle, you also get to reuse the frame of your house. For ground mounts you have to recreate a frame and foundation from scratch. The foundation is important because you don't want the solar panels to go flying when the wind kicks up. Ground mounts are also subject to setback requirements from property lines and other stuff.
For batteries with $0.11/kWh grid electricity, you have to justify your purchase other ways, like "i really need emergency power"
I think net metering plans are balkanized in Texas so you have to dig into your individual situations.
I think you will want to play around with PVwatts to see what kind of generation is possible with your location in the summer. Maybe you can take the edge off your AC. And then for winter production, maybe you can save some minor bucks as a bonus.
BTW wall (vertical) is going to be terrible in the summer. And mounting on wall/ground is going to be costly/complicated compared to roof mounting. Roof mounting has the greatest economy of scale in parts and in permit-ready processes (IE getting people to draw plans for you, for low cost equipment). Fundamental cost angle, you also get to reuse the frame of your house. For ground mounts you have to recreate a frame and foundation from scratch. The foundation is important because you don't want the solar panels to go flying when the wind kicks up. Ground mounts are also subject to setback requirements from property lines and other stuff.
For batteries with $0.11/kWh grid electricity, you have to justify your purchase other ways, like "i really need emergency power"
1st time cost guess: growatt 6kw grid tie inverter MIN 6000 TL-x $749, used solar panes for 6kw ~ $3000, equipment to mount and install: $2000, electrician to tie in: $1000.
Total cost as a guess: ~ $8000
am i missing any significant cost ?
zanydroid
Solar Wizard
That looks high for used solar panels.
$1000 for electrician might be low for a DC system given how much conduit work is needed, and having to add random stuff like rapid shutdown switches (low voltage though).
Or do you just mean final connection into like a main panel, and you do all the electrical?
$1.33/W-DC for DIY if roof mount and outsourcing zero labor is a pretty comfortable price point.
You also pocket the full 30% tax credit as a DIY (rather than passing it on mostly as markup to the installer)
$1000 for electrician might be low for a DC system given how much conduit work is needed, and having to add random stuff like rapid shutdown switches (low voltage though).
Or do you just mean final connection into like a main panel, and you do all the electrical?
$1.33/W-DC for DIY if roof mount and outsourcing zero labor is a pretty comfortable price point.
You also pocket the full 30% tax credit as a DIY (rather than passing it on mostly as markup to the installer)
I found below on the electric company website ( Entergy texas website).
www.entergy-texas.com
After Entergy Texas' approval of the customer's qualifying generation facility, as necessary, Entergy Texas will update the current meter to a bi-directional meter. Unless the customer chooses an alternate metering arrangement as allowed by Schedule SQF, the updated meter will separately register both the amount of electricity purchased from and supplied to the Utility.
For qualifying renewable energy resources with a design capacity of 50 kilowatts or less and for which interconnection agreement was initiated on or after November 29, 2017, the customer will be billed for all energy (kWh) supplied by the Utility and will be credited for any energy (kWh) supplied to the grid in accordance with Option 2C of Schedule SQF unless otherwise specified by the customer. The customer will receive a credit for all energy (kWh) supplied to the grid during the billing cycle based on Entergy Texas’ standard rates for purchases at Avoided Cost. For current Entergy Texas Avoided Cost Data Filing, please click here.
Below are the 2023 avoided cost buy back rates:
2023 Summer Rate $.05322 Cents per kWh
2023 Winter Rate $.050725 Cents per kWh
Notes:
Net metering for renewable energy resources
www.entergy-texas.com
After Entergy Texas' approval of the customer's qualifying generation facility, as necessary, Entergy Texas will update the current meter to a bi-directional meter. Unless the customer chooses an alternate metering arrangement as allowed by Schedule SQF, the updated meter will separately register both the amount of electricity purchased from and supplied to the Utility.
For qualifying renewable energy resources with a design capacity of 50 kilowatts or less and for which interconnection agreement was initiated on or after November 29, 2017, the customer will be billed for all energy (kWh) supplied by the Utility and will be credited for any energy (kWh) supplied to the grid in accordance with Option 2C of Schedule SQF unless otherwise specified by the customer. The customer will receive a credit for all energy (kWh) supplied to the grid during the billing cycle based on Entergy Texas’ standard rates for purchases at Avoided Cost. For current Entergy Texas Avoided Cost Data Filing, please click here.
Below are the 2023 avoided cost buy back rates:
2023 Summer Rate $.05322 Cents per kWh
2023 Winter Rate $.050725 Cents per kWh
Notes:
- Summer Months are May through September and Winter Months are October through April.
- Payments are prorated for seasonal change in price for the transition months. (Example: Billing cycle is April 15-May 15th. The credit will be paid at the winter rate for April kWh and summer rate for May kWh).
- Updated avoided costs estimates are generally filed each February.
Hedges
I See Electromagnetic Fields!
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So you pay $0.11/kWh and are credited $0.05/kWh for backfeed?
A grid-tie inverter will let you use its power while the sun shines, and backfeed what you don't use.
If you buy the hardware and DIY the install (so labor free), I think you can achieve break-even in 4 to 10 years (depending on what you spend for hardware.)
There are batteries-optional hybrids, which will cost more than a grid-tie inverter, and let you add a battery now or later for backup. You could put protected loads downstream of the inverter, and unprotected loads upstream would use surplus production before it reaches the meter.
chrisski
Solar Boondocker
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I disagree that working with the town inspections for both the fire dept and electrical are easy, at least in my local area.
It is easier with a system your AHJ is used to installing. By far the number of installs mine sees is a Tesla powerwall.
I am having an Outback Radian installed and the inspectors are on the fourth trip out. The Outback is UL approved and came from the factory with the SCC installed. The AHJ had the installer replace the factory installed wire between the inverter and SCC.
On a different install, an Enphase system, Enphase allows 6” spacing by the install instructions, but the fire dept insists on 3’.
In both cases, the AHJ could be appealed and perhaps accept the UL improved install, but AHJ has final say.
Might not be worth “fighting city hall.”
It is easier with a system your AHJ is used to installing. By far the number of installs mine sees is a Tesla powerwall.
I am having an Outback Radian installed and the inspectors are on the fourth trip out. The Outback is UL approved and came from the factory with the SCC installed. The AHJ had the installer replace the factory installed wire between the inverter and SCC.
On a different install, an Enphase system, Enphase allows 6” spacing by the install instructions, but the fire dept insists on 3’.
In both cases, the AHJ could be appealed and perhaps accept the UL improved install, but AHJ has final say.
Might not be worth “fighting city hall.”
zanydroid
Solar Wizard
That’s a very annoying AHJ to work with.
I think the issue is that people that come to the forum don’t necessarily have the right intuition on the code compliance costs and don’t sample enough build threads to see how to figure out what it will end up being in their specific town.
I think the issue is that people that come to the forum don’t necessarily have the right intuition on the code compliance costs and don’t sample enough build threads to see how to figure out what it will end up being in their specific town.
