Best Solar+Storage option in the market?

[PVfarmer]

If you're trying to disprove ggunn's statement above:

I've surveyed over a thousand houses for solar, and I can speak from experience that the methodology used for estimating the resource, which takes less than a 1/2 hour, works pretty well.

Neither one of you has any experience with wind- you are solar people.
So it is obvious why you don't like wind.
However, your arguments against it are pretty vague.
In some places solar is better than wind.
In other places WIND IS BETTER THAN SOLAR!

But in the majority of places, they complement each other quite well.
---
An early version of NCAR’s forecasting system was released in 2009, but last year was a breakthrough year—accuracy improved significantly, and the forecasts saved Xcel nearly as much money as they had in the three previous years combined. This year NCAR is testing a similar forecasting system for solar power.

The resulting über-forecast is more accurate than any of the original ones. Then, using data about how much power each turbine in the field will generate in response to different wind speeds, NCAR tells Xcel how much power to expect, in 15-minute increments, for up to seven days. Forecasting solar power is next for NCAR and Xcel, but that can be even trickier than wind.
https://www.technologyreview.com/s/526541/smart-wind-and-solar-power/

 

[PVfarmer]

My general answer on how to integrate wind into a micro-grid system is that it either makes no difference to the over-arching decisions, or it makes it harder.

And what experience are you basing that on?

 

[electrofelon]

Neither one of you has any experience with wind- you are solar people.
So it is obvious why you don't like wind.
However, your arguments against it are pretty vague.
In some places solar is better than wind.
In other places WIND IS BETTER THAN SOLAR!

I think the key thing you are missing is its not just about energy output. Lets even ignore how small wind manufactures chronically fudge their energy numbers (the Eoltec Scirocco was the only one I have heard about that actually had very realistic production numbers). The capital, maintenance, and longevity costs come into play too. The vast majority of people dont want a side job as a power producer. Show me a wind setup that will be mostly maintenance free for 25 years, will produce the energy it is supposed to, and will cost less than solar, and I will certainly be on board.

 

[jaggedben]

...
---
An early version of NCAR’s forecasting system was released in 2009, but l...

This is about grid management. It has nothing to do with predicting energy resource for net metering projects or microgrids. NOTHING. It's really annoying when you just do a google search for language that resembles something you want to make a point about but have no real comprehension of.

As for experience setting up microgrids, you're right, I don't have any real experience, other than receiving some training from manufacturers to become a certified installer, but then ... you have even less. Or else you'd have some concrete suggestions about the best way to do it, which is what the OP asked for.

 

[PVfarmer]

Lets even ignore how small wind manufactures chronically fudge their energy numbers (the Eoltec Scirocco was the only one I have heard about that actually had very realistic production numbers).

The capital, maintenance, and longevity costs come into play too.

Show me a wind setup that will be mostly maintenance free for 25 years, will produce the energy it is supposed to, and will cost less than solar, and I will certainly be on board.

Let's not, and instead just cut their numbers back 10, 20 or 40%, and see that they are still feasible.

There's a $1500 model from someone with the same 5 year warranty as Bergey.

How about a 10-year payback on a turbine that costs 50% more than PV?
PV doesn't work at night.

This is about grid management. It has nothing to do with predicting energy resource for net metering projects or microgrids. NOTHING.

As for experience setting up microgrids, you're right, I don't have any real experience, other than receiving some training from manufacturers to become a certified installer, but then ... you have even less. Or else you'd have some concrete suggestions about the best way to do it, which is what the OP asked for.

Then *why* do you keep mentioning lack of accurate predictions as a reason not to do wind?

I did already give some suggestions to the OP, unlike yourself.
Here are more- there aren't many (UL listed) options for wind inverters, and using a 400V battery system seems silly when the turbines don't output at that level.

You use 400V batteries for solar, and 48V for wind.

What are the different types of grid tie inverters out there?

For your consider, we have compiled a few reviews from our Community Forum members. We attached Member names to specific reviews so you can contact the reviewer directly if you have questions. Links to information about other GTIs has been provided (thanks to Forum Member Minnesota for the links to the UL-approved GTIs listed here). Although this list is not exhaustive, it is a compilation of the GTIs mentioned most regularly by our most active Forum members.
Please note that our lawyer has asked us to remind you:
WindyNation does not endorse the practice of using unapproved GTIs or of tying into the grid without notifying your utility company.

https://www.windynation.com/jzv/inf/learn-about-grid-tie-inverters-wind-turbine-power

Power-One Aurora Wind 3000W	$1,622.92
SMA Windyboy 2000W	No results.
Outback GTFX 2500W	$1659
GINLONG GCI-2K 2000W	$1,500

https://www.windynation.com/jzv/inf/grid-tie-inverters-grid-tie-inverter-pricing-reviews

 

[ggunn]

Neither one of you has any experience with wind- you are solar people.
So it is obvious why you don't like wind.

That is patently false. I like wind just fine when and where it works. Unfortunately, in the Small Wind market there is a lot of charlatanism (not that solar is completely free of it, either) that takes advantage of the lower predictability of wind resource at any given location so when they sell a piece of junk that wouldn't produce even if the resource were adequate they have no accountability. When I design a solar array I know within pretty tight tolerances what it will produce, and my company provides monitoring, so if a system underproduces we roll a truck to go out and see why that is.

BTW, some of have asked, more than once, for you to show your credentials. You write expansively about solar, for example, but I see no evidence that you have any real world experience in the field. I do not have a lot of experience with Small Wind, but do I have some, and what I experienced was dismal.

Also, wind and solar are not in competition with each other.

But in the majority of places, they complement each other quite well.

Upon what data do you base that sweeping statement? Even the wind maps you talk about do not support it.

 

[GoldDigger]

The Windyboy links above to sma-america.com do not work. If you go to the main sma-america page and search for "windy" you will find links to the files and pages at sma.de.

Sent from my XT1585 using Tapatalk

 

[jaggedben]

PVFarmer, I gave my suggestions to the OP in post #3. And several of those suggestions could accommodate wind.

I admit that feeding your trolling on wind has been unproductive. The OP asked a question about integrating sources into a backed up microgrid, not the efficacy of different sources. I don't think you have anything to contribute to that, but try to keep your comments focused on it if you do.

 

[PVfarmer]

Unfortunately, in the Small Wind market there is a lot of charlatanism (not that solar is completely free of it, either) that takes advantage of the lower predictability of wind resource at any given location so when they sell a piece of junk that wouldn't produce even if the resource were adequate they have no accountability.

Also, wind and solar are not in competition with each other.

Upon what data do you base that sweeping statement? Even the wind maps you talk about do not support it.

Why are you implying that "charlatanism" is going on here?
The OP has a wind engineer, and you seem to be stating the obvious, repetitively.

Why are you acting like they are in competition then?

Data? There are *many* "profitable" small turbines in each of all 50 states, how's that?

not the efficacy of different sources.

Well golly, then why are you trying to convince the OP that wind is less efficient than solar?

 

[ggunn]

Why are you implying that "charlatanism" is going on here?

I'm not. I'm speaking of Small Wind in general. Caveat emptor.

The OP has a wind engineer, and you seem to be stating the obvious, repetitively.

Why are you acting like they are in competition then?

Sorry, I don't know what you mean by that. BTW, the OP said his wind engineer has little or no experience with Small Wind.

Data? There are *many* "profitable" small turbines in each of all 50 states, how's that?

Show me the numbers from an independent source. Also show me how many "unprofitable" small turbines there are in the US. I'll wager that the latter outnumber the former by a significant margin.

Well golly, then why are you trying to convince the OP that wind is less efficient than solar?

Apples to oranges. For solar one can by looking up data from NREL and doing some quick and simple shade studies predict very accurately what a PV system will produce. Not so for wind, so again, caveat emptor. It has nothing to do with efficiency, necessarily. One reason a customer of a small wind turbine doesn't get the production he expected could be because his wind resource isn't what he thought it was. Another could be that the turbine he bought is a pretty spinning piece of junk.

 

[PVfarmer]

Caveat emptor.

BTW, the OP said his wind engineer has little or no experience with Small Wind.

Show me the numbers from an independent source. Also show me how many "unprofitable" small turbines there are in the US. I'll wager that the latter outnumber the former by a significant margin.

Apples to oranges. For solar one can by looking up data from NREL and doing some quick and simple shade studies predict very accurately what a PV system will produce. Not so for wind, so again, caveat emptor. It has nothing to do with efficiency, necessarily. One reason a customer of a small wind turbine doesn't get the production he expected could be because his wind resource isn't what he thought it was. Another could be that the turbine he bought is a pretty spinning piece of junk.

Buyer beware?
I was not aware the OP's customer is following this thread. (Because they aren't? :huh: )

I'm sure the OP's engineer has more experience than either of us!

How about you showing us your numbers? You don't like it when I post links- however, you can go right ahead.
It seems like you are either warning the OP not to get ripped off by the Chinese, or saying the customer is going to be disappointed by wind no matter what- neither of those things seem terribly relevant to high voltage lithium batteries.
Do you have any good reasons why using 400V batteries with 48V turbines is a better setup in any way? That would be more on topic...

The bold part is simply false.
Click here.
http://www.nrel.gov/analysis/models_tools.html
[h=1]Models and Tools[/h] Use models and tools developed or supported by NREL to assess, analyze, and optimize renewable energy and energy efficiency technologies for your project. Many of these tools can be applied on a global, regional, local, or project basis. NREL models and tools include several designed for the consumer or energy professional.


or here:
https://www.nrel.gov/grid/wind-integration-data.html

 

[wwhitney]

https://www.nrel.gov/grid/wind-integration-data.html

If you follow this link and click "learn more about the data sets", you will find out that, for example, the western data set is gridded at one point per square arc-minute (1.15 miles, or 1.32 square miles).

So I think the point several others have made here is that available wind resource will vary at a much finer scale: different sites within any given square mile may have much different available wind resource. That means that while the NREL data set will give you an initial estimate, a site specific long term survey would be appropriate before actually committing resources.

And if I understand correctly, solar is much less variable. Absent clouds and site shading, it seems to me it would be 100% predictable. Site shading is easily established from a single site visit. So I infer either (properly time weighted) average daytime cloud cover varies geographically much less than available wind resource, or the NREL data is more finally gridded for average daytime cloud cover, or both.

Cheers, Wayne

 

[ggunn]

How about you showing us your numbers? You don't like it when I post links- however, you can go right ahead.

You made the statement, you prove it.

 

[ggunn]

If you follow this link and click "learn more about the data sets", you will find out that, for example, the western data set is gridded at one point per square arc-minute (1.15 miles, or 1.32 square miles).

So I think the point several others have made here is that available wind resource will vary at a much finer scale: different sites within any given square mile may have much different available wind resource. That means that while the NREL data set will give you an initial estimate, a site specific long term survey would be appropriate before actually committing resources.

And if I understand correctly, solar is much less variable. Absent clouds and site shading, it seems to me it would be 100% predictable. Site shading is easily established from a single site visit. So I infer either (properly time weighted) average daytime cloud cover varies geographically much less than available wind resource, or the NREL data is more finally gridded for average daytime cloud cover, or both.

Cheers, Wayne

Thanks; that is exactly what I have been saying about wind resources vs. solar resources. Couple that with the shady reputation of many vendors of small wind turbines and their lack of accountability, and it yields a very risky result. The OP's customer may not care about the risk and may just want a toy that may not ever pay for itself; in that case I'd tell him to go ahead but the risk is on him.

 

[jaggedben]

Let's try to go bigger picture and get this more or less back on topic...

If you put in an alternating current microgrid as covered in the latter part of article 705 of the 2017 NEC, then you can hook up any interactive sources within it - solar, wind, fuel cell, whatever - and use a battery inverter(s) as your primary source. You either have to have each source support some kind of protocol for throttling power if there would be too much - there are some that exist but aren't much followed in the US - or you have to not oversize the energy sources too much compared to the batteries' charging rate. Asking questions about battery voltages is not necessary for this exercise. Tesla, SMA, Outback, and some others support this sort of thing, with Tesla to my knowledge having a much better pass through current rating from the utility when the micro-grid is not islanded.

If you want to have a DC coupled system then your options are going to be quite limited by comparison. That sort of thing is usually not going to be a better option unless your goals for backup power are limited to a refrigerator and a bit of lighting.

 

[ggunn]

...with Tesla to my knowledge having a much better pass through current rating from the utility when the micro-grid is not islanded.

But good luck procuring one.

 

[PVfarmer]

That means that while the NREL data set will give you an initial estimate, a site specific long term survey would be appropriate before actually committing resources.

There's the OP's customer with some property and limitless funds- the only real question would be what's the best spot on the property.
The learn more about the data link also says-

These data sets may not match the distribution of the wind resource shown on U.S. Department of Energy state wind maps. The state wind maps depict the distribution of long-term average wind resources, whereas these data sets were designed for use in wind integration studies that examine temporal profiles of wind and load.

These data sets are time-series data for 2004, 2005, and 2006. This means that if you are investigating an overall good wind site but, for example, 2004 happened to be a bad year for that site, then the time-series results for 2004 will likely reflect the poor resource during that year. Conversely, 1 year of data from this wind data set might show a good wind resource due to interannual variations, yet the long-term average resource may be lower. The goal of these data sets was for use in wind integration studies that examine wind profiles with load or other wind. The goal of the wind maps is to depict the distribution of long-term average wind resources. These time-series data sets and the wind maps were created for different goals and cannot be directly compared.

You made the statement, you prove it.

Thanks; that is exactly what I have been saying about wind resources vs. solar resources. Couple that with the shady reputation of many vendors of small wind turbines and their lack of accountability, and it yields a very risky result. The OP's customer may not care about the risk and may just want a toy that may not ever pay for itself; in that case I'd tell him to go ahead but the risk is on him.

It's actually not relevant, why not drop it?

Limitless funds? Get a Bergey. Why not? The payback might very well be < the 10 year warranty.

Don’t I have to take wind measurements for a year or more?
No. For residential systems the cost of taking wind measurements is not justified in most situations. Wind resource data published by the U.S. Dept. of Energy is sufficient to predict performance. In very hilly or mountainous areas, however, it may be prudent to take wind data before purchasing a system to ensure that your site in not in a sheltered area.
Are wind turbines reliable, and what about maintenance? Bergey Windpower sells more residential systems than anyone else because our turbines have proven to be the most reliable on the market. Our turbines have only 3 or 4 moving parts and do not require any regular maintenance. After a 66 month test of one of our 10 kW units, Wisconsin Power & Light concluded that, “The turbines’ reliability could not be improved upon.” Our turbines are designed to last 30-50 years or more and they operate completely automatically.
http://bergey.com/wind-school/residential-wind-energy-systems

get this more or less back on topic...

Asking questions about battery voltages is not necessary for this exercise.

If you want to have a DC coupled system

Integrating high voltage lithium batteries is the topic the OP is asking about, and it's their thread!
Did they ask about DC coupling? Nope.

 

[ggunn]

Whatever.

 

[jaggedben]

...

Integrating high voltage lithium batteries is the topic the OP is asking about, and it's their thread!
Did they ask about DC coupling? Nope.

Those two sentences are contradictory. If you are not doing DC coupling then you aren't concerned about matching battery voltages.

By the way, there's only one manufacturer in the US, to my knowledge, which does DC coupling for solar at high voltage. That is SolarEdge. All other DC coupling is low voltage. AFAIK, there is no equipment that is similarly designed for wind. I guess there's a few wind inverters that could be used in an AC coupled system.

 

[ggunn]

Those two sentences are contradictory. If you are not doing DC coupling then you aren't concerned about matching battery voltages.

By the way, there's only one manufacturer in the US, to my knowledge, which does DC coupling for solar at high voltage. That is SolarEdge.

Not any more, I don't think. The StorEdge inverter was specifically designed to interface with the Tesla DC PowerWall, which has gone the way of the dodo. We have a customer who wanted a StorEdge and DC PowerWall system but waited until the DC PowerWall was no longer available. We designed in an AC PowerWall (and are still waiting for Tesla to start shipping them), and I called our SolarEdge rep to ask him if there was any reason to keep the StorEdge in the design. He said no, and I got the distinct impression that SolarEdge is not very happy with Tesla at the moment.

BTW, a couple of years ago I helped design the PV part of a weird hybrid PV and generator system our customer was building that used DC generators to feed the inverters at night. I was with that PV company for another 8 months and I never found out if it ever worked the way it was supposed to.