What are you generating?

Re: What are you generating?

dsp3930 wrote: »

I have a 672 watt array. (3 x Sharp ND-224UC1)
I output about 4700 watt hours on April 9th. (according to my Xantrex SCC)
This equates to roughly 6.99 hours at 100% of PV panel rated production.

Sunrise is roughly 7AM. (No trees to the east)
Sunset was roughly 8PM. (Trees start blocking sun at 6:45PM)

I live in the SW corner of Lake Erie ESE of Toledo, OH.

Wow! The closest place to you that approximately had 7.0 sun-hrs on, on April 9th, was many areas in TN.

The insolation map I referenced earlier shows that for ESE of Toledo, insoluation was approximately 4.7 sun-hrs. And looking at a past weather report for Toledo for Apr. 9th, it said it was windy and cloudy, with a high of 49°F. So the weather reports seems to match my interpretation of the insolation map for your location.

Doing the calculation to determin 'apples-to-apples' efficiency:

4.7 kWh produced / 4.7 sun-hrs insoluation / 0.672 KW = 150% efficient.

Obvisouly 150% doesn't make sense, and thus you must have had a lot more insolation that 4.7 sun-hrs. In fact, if you assume 90% efficiency, then you had about 7.8 sun-hrs of insolation. I looked on the map across the entire U.S. but couldn't find any location with that much sun (on Apr. 9th). So there must be something wrong with my analysis or the 4.7 kWh produced from 672 panel watts.

Interesting subject.

Best regards,

Bill

Re: What are you generating?

drees wrote: »

Anyone able to find a source of irradiance data for specific times/dates like the data that mikeo used to plot the chart he posted earlier without buying a meter?

For spot checks, I've found two handheld devices:

Daystar DS-05A $144

General Tools DBTU1300 $117

Otherwise for data gathering, the Davis weather stations can be had with Irradiance sensors, but then you're looking at $660+ from what I can tell.

Even what Mikeo has isn't what you really want, unless you have some way to integrate the solar irradiance values for the day (which equals insolation for the day).

I couldn't find an online source that reports a day's insolation for a given location other than what I reported earlier.

With respect to an instrument, you need something that does measuring across the entire day. It needs to sample at a reasonable frequency (i.e., once per minute), and needs to be able to accumulate the values to sum into an insolation for the day amount.

Here is such an instrument: http://www.microcircuitlabs.com/SDL-1.htm , at $160. It does the measuring of solar irradiance at a selectable frequency (10, 60, 150, 300 or 900 sec.), and does the integration of the values to produce a daily insolation result (updated hourly). All in a weatherproof case.

Best regards,

Bill

Re: What are you generating?

We sure need a rain to clean off the panels at my location. The Oak pollen has a yellow haze over everything so my solar output has diminished to just over 9 KW each day, otherwise I think I would be getting over 10 KW. due to clear skies, low humidity and bright sun. It's always something!

Re: What are you generating?

Interesting, I have been thinking about a weather station for quite a while and the comments on the Davis one got me thinking again.

Off to eBay just to check it out

Top of the line Davis pro2 plus wireless with active fan cooling lists for $1195 is all over eBay for $1075.

I had never tried a best offer before so I submitted what I thought was a pretty good low ball offer, $950 including shipping and mounting hardware.

BOOM offer accepted, now I wish I had gone lower :roll: The one I picked is probably way over kill. I did see a used older model Pro listed for $100, but you would need to add the solar sensor to it.

If your really interested looks like you can easily discount on these guys by 12%+.

http://shop.ebay.com/rjnetsale/m.html?_nkw=davis+weather+station+pro2&_sacat=0&_trksid=p3911.m270.l1312&_odkw=&_osacat=0&bkBtn=

Re: What are you generating?

mikeo wrote: »

You are not quite done yet! You will need a Weatherlink software package and data logger. You buy the software and they throw in the data logger. You have 3 choices, serial USB and WLIP. With WLIP you don't need to run a computer continuously to log data, it is sent to Davis Server at 15 Minute intervals. You just need a empty router port to plug it in. With all options you can log data with a dedicated computer and send at shorter intervals and to more website options then Davis offers. Check out the CWOP site for much more infomation.

LMAO it is always that way, Yeah I know this doesn't include the data logger components.

From what I see on the Davis site I will need a Windows host to log the solar data to. MAC won't cut it unfortunately. Fortunately I have a low power Windows laptop I can use for that purpose.

Can you tell me if the logging format is open so a USB setup to a MAC might be used with some custom Perl scripts? Does the WLIP offer a possibility of accessing the data via ethernet?

Re: What are you generating?

mikeo wrote: »

Yes WLIP allows access from a PC running Weatherlink and also several 3rd party software packages. I think there maybe is a MAC version of WeatherLink also available. I use WLIP and find that sufficient for my needs. I am a member of CWOP and Weather Underground and the Davis website does support those two groups. I also use Weatherlink on my PC to download and maintain a historical weather database. I only need to run it once or twice a month. I highly recommend CWOP because they send a daily quality report on your data that helps keep the data calibrated and accurate. I have my DSL modem/router and WLIP powered with a 12 volt battery and plugged into a wall charger so if power goes out, the weather data is still sent.

the Davis site clams the MAC version won't log the solar data (or several other sensors). Think I will give them a call today to get a better understanding, I would prefer to not setup a windows host just to get that data.

Does the CWOP report your solar data as a downloadable set of values? If so that should be adequate.

Re: What are you generating?

mikeo wrote: »

Yes if 15 minute resolution is sufficient. You can download the data into a spreadsheet and manipulate it from there.

Yeah that is probably close enough for government work. :D

Re: What are you generating?

nvyseal wrote: »

@solar dave, Can't you use bootcamp and XP on the mac?

That is an ugly solution, Windows is not my favorite player. Plus I have stuff on my MAC that runs pretty regularly to collect my TED data ( now to flat files, soon to DB )

PS my wife who is not very computer literate Says "Bill Gates is the spawn of the Devil"
She got virus infected all the time when on Windows.

Re: What are you generating?

BB. wrote: »

For me, the first I heard of viruses was from the Original B&W Macs... We were all using PC's and Unix boxes in engineering.

However, the read anything off the disk and run it did turn out to be one of the worst design flaws once hard disks and networks/modem were common to small computers.

-Bill

Yeah the concept of kernel hooking via dll and running all in admin/root space is just a bad model. This is one of the reasons the security stuff on a MAC simply works.

Re: What are you generating?

RandomJoe wrote: »

You might try wview:
http://www.wviewweather.com/

It has an OSX port. I use it on Linux for my Vantage Pro 2. There are option switches to enable logging "extended" sensors including the solar ones. It also creates webpages of the data, so you can easily see it remotely, if you wish.

You still have to buy the Windows software to get the serial or USB interface, of course...

Now this is cool, thanks for the link.

Re: What are you generating?

solar_dave wrote: »

That is an ugly solution, Windows is not my favorite player. Plus I have stuff on my MAC that runs pretty regularly to collect my TED data ( now to flat files, soon to DB )

PS my wife who is not very computer literate Says "Bill Gates is the spawn of the Devil"
She got virus infected all the time when on Windows.

Why in the world would any self-respecting Mac user want to run Windoze on his machine? That's why we went Mac in the first place - to get away from that stuff!

Re: What are you generating?

It just keeps getting better ... 5.00 kw generated today. (96ah according to the Xantrex SCC) 3 Sharp 224w ND-224UC1 panels

It looks like we will hit about 460kwh billable for the month after accounting for the solar generation. Once I get my other nine panels in, I should see summer peaks of 20kwh generated per day. (I use about 21kwh per day) Eventually, I'd like to get about double that to offset the really crappy winter generation in Ohio. (I'll see about 2-4kwh per day average from OCT/NOV to FEB/MAR off 12 total panels.)

Re: What are you generating?

Tornadoes ripped through Central Arkansas tonight killing at least 3 people and injuring a dozen more. Power is out and I am running on my Battery back up. This is why I have a Hybrid system. Power may be restored tomorrow, or it may take a few days. Worst case for me is 21 day with out power after an ice storm.