Best Solar+Storage option in the market?

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bbartmasse r

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Washington State
Hello,

If you had a client with limitless funds and wanted to serve as a guinea pig for the industry which Solar+Storge options would be good?

Would it be possible to combine wind power into one of these systems with a high voltage battery?

thanks

Brett
 
Do not expect a real contribution from wind in most of the country.
And plan on a 60' or higher tower.
In general even with the right conditions small wind is only viable when you are completely off grid and must have something to supplement PV in the dark winter.

Sent from my XT1585 using Tapatalk
 
In my opinion Tesla has the best solution, if you can get it. If your customer truly has limitless funds and wants whole-house-backup on a large house, I'm sure the number of Powerwall units required will get their attention. The solar is basically installed separately, and can be anything you want, which is a good thing in my opinion.

As far as other options:

SolarEdge+LG Chem is probably the most user friendly to set up, but is limited in terms of total system power and energy. Only 25A output.

For technologies that have a good track record but are less cutting edge, look at Outback or the SMA Sunny Island. Those systems are customizable and scalable but require quite a bit of experience and expertise. I think Tesla's solution -and the eventual copycats - will make them obsolete once price/availability issues are worked through.
 
Perhaps I should add: in my first post I assumed your client is connected to the grid and just wants backup-capability or energy management. If this is for a truly off-grid system then the equation favors Outback or SMA. Not exactly 'guinea pig' territory with those, if you can find an engineer with experience...
 
GoldDigger said:
with the right conditions small wind is only viable
Click to expand...

But one of the conditions here is limitless funds!
Doesn't that make everything viable? :)

You can pay between ~ $1000 and $4500 for a 1kW windmill.
If it takes 20 years to pay for itself, ok, in this case funds aren't the issue, generation on cold windy winter nights is.

This Sonnenbatterie system is pretty cool.

Drawing exact comparisons between battery products is difficult. For one thing, Sonnen’s eco batteries are priced as 4-kilowatt-hour packs, which are smaller than Tesla’s 6.4-kilowatt-hour Powerwall. The batteries also have slightly different life cycles. Sonnen offers a warranty for 10 years, or 10,000 cycles with 100 percent depth of discharge and 70 percent capacity (equal to 2.8 kilowatt-hours) remaining at the end of the term.
Tesla’s Powerwall warranty lasts for 10 years, or 5,000 cycles, with a step-down scheme. The manufacturer’s warranty in Australia (which is no longer available online) reveals that the policy covers 740 cycles or 85 percent of 6.4 kilowatt-hours (equal to 5.4 kilowatt-hours) of capacity for the first two years -- whichever comes first. Then it covers 4.6 kilowatt-hours for three years or 1,087 cycles. And finally, it covers 3.8 kilowatt-hours or 60 percent for five years or 2,368 cycles.
"The $6,000 price point for Sonnen's 4 kilowatt-hour system not including installation (or roughly ~$1,500/kWh, sans installation) is competitive with other offerings in the U.S. residential market today when taking into account the fact that Sonnen's new system is warrantied for 10,000 cycles, which is greater than the cycle life warrantied by some of their competitors," said Brett Simon, energy storage analyst at GTM Research.

https://www.greentechmedia.com/arti...-Battery-for-Self-Consumption-at-a-40-Reduced

http://www.windpowerengineering.com...en-battery-ready-ready-off-grid-applications/
 
PVfarmer said:
But one of the conditions here is limitless funds!
Doesn't that make everything viable? :)
Click to expand...

Um, no. Most (all?) Chinese small wind turbines are junk and will never pay for themselves. Furthermore, just because the wind seems strong and/or steady at a particular location, that doesn't mean you have a harvestable wind resource. Solar resources are well documented, so the yield of a solar array at a given location and orientation is predictable to a fair degree of accuracy; not so for wind. Most people who buy small wind turbines get ripped off.
 
Here are some pricier windmills: http://bergey.com/documents/2013/10/bwc-retail-price-list-10-01-13.pdf

Note there's the 7.5kW model that outputs 240V DC.

And here is the lower cost side.

"When small wind turbine generating 1kW energy costs INR 3-7 lakh (US$4,000-10,000), our company plans to sell it at less than NR 50,000 (about US$750). Costs will decrease further through mass production," Arun said.
http://www.1millionwomen.com.au/blog/low-cost-wind-turbine-power-entire-house-lifetime-starts-selling-india/
 
The difference is:

Solar resource can be estimated to within about 5% by using wide area meterological data. The only thing that needs to be done on site is taking shade factor readings, which can be done in about 15 minutes. The total variance among sites in the continental US usually doesn't vary by more than a factor of 2.

To properly estimate wind resource, you really need to set up instrumentation on the actual site and gather data for a year.

Edit: I think the OP is asking about the US market, not India.
 
ggunn said:
Chinese small wind turbines are junk and will never pay for themselves.

Furthermore, just because the wind seems strong and/or steady at a particular location, that doesn't mean you have a harvestable wind resource.
Solar resources are well documented, so the yield of a solar array at a given location and orientation is predictable to a fair degree of accuracy; not so for wind.

Most people who buy small wind turbines get ripped off.
Click to expand...

I didn't say anyone should buy imported junk windmills.
However, there are some from China which are certainly OK.

You can use NREL SAM for wind just the same as solar.
There are also maps one can find easily
http://www.nrel.gov/gis/images/30m_US_Wind.jpg

Anyone who wants to can look up windmills on their own and decide how much they want to spend, instead of getting ripped off.

If someone wants to spend $4500 on a USA-made 1kW model and it takes 15 or 20 years to pay for itself...so what?

This one here might produce 18,000kWh a year- so what's the bill? How much is being saved, is there a feed-in-tariff?
At .20 cents/kWh, that's $3,600 a year.
$21,900 / $3600 = a 6 year payback!


Cost: $21,900-$27,900


Rated Capacity: 10kw
Startup Windspeed: 7.5 mph
Rotor: 22 feet (6.7 m)
Interconnection: Utility connected or battery charging
Voltage Output: 48 VDC or 120, 240 VAC
Estimated Energy Production: 1500 KWh/month @12.5mph
*Note: Prices listed are the manufacturer’s suggested retail price, it is quite possible to find them for less (nobody pays retail anymore, right?)
https://cleantechnica.com/2008/03/21/the-five-best-micro-wind-turbines/3/
 
jaggedben said:
Solar resource can be estimated to within about 5% by using wide area meterological data.

The only thing that needs to be done on site is taking shade factor readings, which can be done in about 15 minutes.

The total variance among sites in the continental US usually doesn't vary by more than a factor of 2.

To properly estimate wind resource, you really need to set up instrumentation on the actual site and gather data for a year.

Edit: I think the OP is asking about the US market, not India.
Click to expand...

People (meteorologists in fact) have been measuring and recording wind speeds for longer than they have solar irradiance.

All you have to do with wind is go 60+ feet, or higher than that if there are 60+ foot trees.

Not sure what that is in regards to.

Yes, you can set up instruments for a year- or you can look at a map and lowball it.

The point is, if you can build a shed or chicken coop, you can quite probably build your own windmill. That's what the Indian fellows have done.
For $750/1kW, putting 2 of them at 30' height is cheaper than one $4500 USA built model at 60'.
Six times cheaper, in fact.

Not saying the OP should build one- just saying there are cheap and 100% viable options. Everywhere.
 
Wind resources can vary widely between locations which are very close to each other; I certainly wouldn't invest in a turbine without doing a wind study for at least a year in the exact location the turbine would go. I also wouldn't invest in a turbine without a lot of real world production data from that specific model. Actually, I wouldn't invest in a small wind turbine at all, but you may do what you like.
 
ggunn said:
but you may do what you like.
Click to expand...

1- OP said limitless funds.
2- Sounds like the wind decision has been made by the person who has #1.

The OP's question was can windmills be used with higher voltage batteries, the answer is yes.

However, if you do want a highly detailed wind map of your own state, click on it here.
Waiting a whole year for data is overdoing it in my book.

WA state (the OP) has the same range of wind speeds as RI does- 5 to 10 m/sec.
So does your own state.

https://apps2.eere.energy.gov/wind/windexchange/wind_maps.asp
 
thanks for the replies.

Our company is not new to solar, and has extensive knowledge of off grid systems. Mainly with lead acid batteries because that has been what has worked for years.

This customer has a wind fetish and a lot of money, I think a 100 foot tower would not be a problem.

we also are well aware of the pitfalls of wind, and have a wind engineer on our design team with years of experience with large scale wind projects, not much residential stuff though.

What we don't have much experience with are the newer lithium batteries combining with a grid tied inverter. And I do not think we have ever done a grid tied wind system, only fully off grid.

The client is interested in how a house or group of houses can show that we can be energy independent but still wants to be connected to the grid.

As you might guess, they are a bit of a dreamer type, but hey, why not?

thanks
 
One thing you need to carefully consider with respect to a wind powered GTI system is that GTIs pretty much universally have MPPT input sections designed to work with the current voltage curve of solar panels.
There is no energy storage mechanism in a PV array. When you change the effective resistance of the inverter input the new voltage and current values will be stable.

With a wind turbine, on the other hand, there is significant energy stored in the rotating mass of the turbine and generator.
That means that when you increase the current drawn from the generator the voltage will not immediately decline to a stable value but will slowly ramp down as the generator pulls more energy from the system than the wind is replenishing. An MPPT algorithm which rapidly changes the operating point can either result in an unstable operating point or an operating point which is not actually optimal.
In addition gustiness of wind speed over a long enough time to allow the turbine speed to change rather than hold an average value can be ignored by an MPPT algorithm that does not retest the operating point frequently enough.

Some Charge Controllers designed primarily for PV operation (Midnite Solar Classic models, for example) have an entirely separate mode of operation for use with wind turbine input which stores a table of voltage versus current points which are selected based on an instantaneous check of the no-load turbine output voltage. This allows the operating point to be tailored to the rotational speed of the turbine. I cannot say from personal knowledge that the result is better, but a lot of wind enthusiasts praise it.

It gets even more complicated when the turbine system includes a voltage regulator circuit which will try to hold the output voltage steady as the input power, turbine speed, and available steady state current vary.

(There is a report of one maker/vendor of small wind turbines who vastly inflated the available power from his machines at any given wind speed:
"They can deliver that power for a fraction of a second while they are slowing down from their equilibrium speed, so the number is honest.")

I am sure that large wind farms and large individual turbines have excellent ways of dealing with these factors, but reproducing that behavior using currently available small GTIs designed specifically for PV use may be a problem.
Similar concerns (although possibly with proportionately lower energy storage?) apply to small hydro systems.
 
PVfarmer said:
1- OP said limitless funds.
2- Sounds like the wind decision has been made by the person who has #1.

The OP's question was can windmills be used with higher voltage batteries, the answer is yes.

However, if you do want a highly detailed wind map of your own state, click on it here.
Waiting a whole year for data is overdoing it in my book.

WA state (the OP) has the same range of wind speeds as RI does- 5 to 10 m/sec.
So does your own state.

https://apps2.eere.energy.gov/wind/windexchange/wind_maps.asp
Click to expand...

The wind maps just dont have enough resolution to be treated as gospel. Sure then can be used as a guide or for rough figures. Perhaps you should ask your client who is paying 40 grand for wind turbine set up if a wind study is over doing it. Very very very few people have a good wind site.

I lived off grid with a wind turbine for 5 years, and spend three years before that researching and planning it out. I would not recommend small wind to anyone, with just about the only exception being if it is hobby you really really like. Even assuming an excellent wind site, The capital costs are very high, and it is unlikely to be maintenance free. I have been up on my tower 80 feet in the air when the wind is blowing 30 MPH and it is 5 degrees out to fix a frayed wire or lubricate the furling pivot. Oh, and its a 1500' hike up a 45 degree slope with two feet of snow to get the base of the tower. IMO the way to go for off grid is an over-paneled PV system, with a modest battery bank, a generator, and an inverter with generator support. Many people make the mistake in off grid of being overly reluctant to run their generator. They either throw lots of money at batteries and panels thinking they can minimize/eliminate generator usage, and/or they hold off running the genny until the batteries are near dead. The key is to instead not sink all that money into a huge battery bank and use the generator to help out "as you go". That is the most cost effective way anyway. If money is not an issue, I guess we would need to know what the goal is then.
 
bbartmasse r said:
What we don't have much experience with are the newer lithium batteries combining with a grid tied inverter. And I do not think we have ever done a grid tied wind system, only fully off grid.

but hey, why not?
Click to expand...

Ok, here you go- there are more inverter options with the 48V lithium model than the 400V, for LG batteries.
Hope that helps. And here's another 48V maker: https://d1819pwkf4ncw.cloudfront.net/files/documents/bmz-usa-ess-70-datasheet-12-1-2015-344595.pdf

This is on the last page of the link below-
400V residential:
Compatible Inverter Brands : SMA , SolarEdge (As of 3Q. 2016, More brands to be added)

48V residential:

Compatible Inverter Brands :
SMA, SolaX, Sungrow, Schneider, Ingeteam, GoodWe, Redback, Victron Energy
(As of 3Q. 2016, More brands to be added)
https://d3g1qce46u5dao.cloudfront.net/data_sheet/ess_lgchem_eng_0_.pdf


electrofelon said:
The wind maps just dont have enough resolution to be treated as gospel.
Sure then can be used as a guide or for rough figures.

Perhaps you should ask your client who is paying 40 grand for wind turbine set up if a wind study is over doing it. Very very very few people have a good wind site.

I lived off grid with a wind turbine for 5 years, and spend three years before that researching and planning it out. I would not recommend small wind to anyone, with just about the only exception being if it is hobby you really really like. Even assuming an excellent wind site, The capital costs are very high, and it is unlikely to be maintenance free. I have been up on my tower 80 feet in the air when the wind is blowing 30 MPH and it is 5 degrees out to fix a frayed wire or lubricate the furling pivot. Oh, and its a 1500' hike up a 45 degree slope with two feet of snow to get the base of the tower. IMO the way to go for off grid is an over-paneled PV system, with a modest battery bank, a generator, and an inverter with generator support. Many people make the mistake in off grid of being overly reluctant to run their generator. They either throw lots of money at batteries and panels thinking they can minimize/eliminate generator usage, and/or they hold off running the genny until the batteries are near dead. The key is to instead not sink all that money into a huge battery bank and use the generator to help out "as you go". That is the most cost effective way anyway. If money is not an issue, I guess we would need to know what the goal is then.
Click to expand...

If the location is smack in the middle of a wind map zone, the reality will be fairly close.
Building codes are based on maximum wind speeds, using the same data, those are legit.

You can say "it'll take 10-12 years to pay back that $40,000, depending on actual wind speeds after installation".
There's no reason to use 6 m/s "as gospel" even in the middle of a 6 m/s zone- you can plug in 5.5 m/s and 5 m/s and see how it affects the $$ with SAM.

Bergey has a 5/10 year warranty, (no customers climbing towers) which is part of the higher price.
http://bergey.com/documents/2012/05/excel-10-warranty-statement.pdf
 
PVfarmer said:
...

If the location is smack in the middle of a wind map zone, the reality will be fairly close.
Click to expand...

Do you state this from experience?

Building codes are based on maximum wind speeds, using the same data, those are legit.
Click to expand...

Wind resource is basically about average wind speed, and has almost nothing to do with maximum wind speed.
 
jaggedben said:
Do you state this from experience?

Wind resource is basically about average wind speed, and has almost nothing to do with maximum wind speed.
Click to expand...

Seems accurate where I live. How about you?
Have you compared yearly output with same equipment/location using both 5 and 6 m/s with SAM?
Isn't how much the difference between 5 and 6 matters financially kind of the customers decision and not yours?

Also- didn't the OP already say they know the pitfalls and have a wind engineer?
So...? :huh:

The same people are collecting the data for both, that is my point.
Average wind speed data is somewhat accurate for the same reason people's roofs aren't blowing off in hurricanes- the historical data exists, in both free/public and private/you pay for it forms.
 
jaggedben said:
Do you state this from experience?



Wind resource is basically about average wind speed, and has almost nothing to do with maximum wind speed.
Click to expand...

And even when you know both maximum and average wind speed, the available power depends on just how the wind speed is distributed around that average.
There is a standard statistical distribution which is used to estimate actual wind speed distribution based on the average, but it does not apply to all areas.
If the average wind speed is the result of some hours of speed too low to produce power and some hours of speed too high to safely operate the turbine, the available power could be zero.
 
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