Blowing up Inverters – Sort of

I now know what I didn't know.  I know what I know.  I don't know what I don't know I don't know.  And I don't care that I don't know what I didn't know but now I know but could get by just fine not knowing.
750-watt inverter working happily after the connection was fixed.  Now on lighter "office duty."
750-watt inverter working happily after the connection was fixed. Now on lighter “office duty.”
The learning curve continues.  

Perhaps I'll have that carved on my headstone.  Seems rather profound without being actually profound (a bit like Donald Rumsfeld).  But I digress.

I have managed to blow up one of the inverters on one of my solar generators.  Not blow up as in it lies in pieces at my feet – but blow up as now when I push the button, nothing happens.  I know why this happened, which is helpful.  My mistake was believing the literature.  The inverter was plenty big enough to handle the job, except that it wasn't.

The information on the internet was wrong (imagine that).  The manufacturer was apparently mistaken – asserting that limited power could handle the problem (why does this all keep reminding me of Donald Rumsfeld?)  

I have fixed the problem by installing an inverter that is rated to handle ten times the power requirements of the refrigerator.  Colin Powell would be proud.

Postscript:  Turns out I didn't know what I knew.  I went to replace the bad inverter – but it turned out to be a bad connection.  The smaller inverter still won't power the refrigerator, but at least it didn't meet its maker... yet.  
Advertisements

Tweaking the Solar Generators

The first full day of Thanks for Nothing has come and gone – and we have once again survived without some of the conveniences of a modern society.  Amazing. 
Annie enjoying dinner by candle light in front of the wood fire.
Annie enjoying dinner by candle light in front of the wood fire.
My role on the first day was largely technical.  As mentioned, we are trying out our solar generators – trying to test them and push them to their limits.  Well, right off the bat we found some limits.

We built three units.  The small unit, complete with a 400 watt inverter, a 35 amp-hour battery and all the other bits and bobs that make it work seems to be doing its assigned job just fine. In fact, I am connected to it as I write this.  For more than a day it has managed to supply power to my laptop, printer, cordless telephone and lamp (see, a complete office if your office consists only of a laptop, printer, telephone and lamp).  

We used the laptop all day – plus watched two movies on it during the evening (actually documentaries – so we are still pure and righteous).  We have also been listening to the radio over the internet on the laptop.   Some day we might actually stream music and join the modern world more completely.  As I type this, the unit just gave out a squawk that it was at the end of its juice.  So 24-hours seems to be the limit on this unit.  That will probably get you through most power outages.

The middle unit is, as you would imagine, a bit bigger.  It has a 750 watt inverter and a 110 amp-hour battery.  We determined to use this for the refrigerator, as our LG fridge only draws about 165 watts when running, I figured this would be more than enough.  But we have learned something about inverters (and motors).  

When the refrigerator kicks on (and this applies to any appliance with a motor), it draws a bit more energy in the first few seconds of operation (a surge).  Our inverter is supposed to handle this, rated to up to 1500 watts for a few seconds, but happier if only providing 750 watts or less on a continuous basis.  

We found that when the refrigerator tried to kick on, the inverter would indicate it was overloaded (even though it was well below its rated limit).  It would do this four or five times, then chug away happy as could be.  I worried that all this might be putting a strain on our refrigerator – so we moved the bigger unit in to take over.

The large unit has a 2,000 watt inverter and a 225 amp-hour battery bank.  The refrigerator is really happy with this unit.  We need to do a bit more testing, but it looks like there needs to be a lot of headroom in inverter capacity when working with motors – much more than the rated watts of the unit might suggest.

So we are off and running, settling into the slower pace of Thanks for Nothing month.  Dinner must be anticipated well in advance and cooked on the wood stove.  It is eaten by candlelight, which is never a bad thing.

Here Comes The Sun

There’s anticipation in the air and it’s not because fall weather makes me nervous that it will frost and finish off the garden. Actually there should be a giant drum role because when we created the first 10 year plan for Blue Rock Station in 1996 we put renewable energy (I barely understood this term) at the end of the goals because it wasn’t an efficient use of money or resources in those days). BUT…In three weeks we will install the solar array that will provide most of the power we will need for the entire farm.

The system we’ve designed is going to be installed in three segments – one the first week of October, and then we’ll add another array in a year, and then, if we need it, another array in 2016. This approach allows us to practice more conservation and also to learn more how we use energy, and how not to go hog wild since it is technically free.

Jay likes to say that when solar energy is readily available (and cheap) people will go crazy using it – “like a bunch of fraternity boys at a party with free booze”. I don’t want to think about energy as “free” because it is not. Many resources (some that are very limited) go in to making the solar array system. Rare minerals are required to create solar panels and those minerals are growing more and more scarce. That’s the reason that the US (and other countries) are exporting used electronics to China – little children are used to extract these rare minerals so they can be re-used. The rare minerals have some very serious side effects when touched by humans. I will leave you to figure out why this isn’t good.

My hope is that this new way of generating electricity will provide us with ways to “think” more honestly about how we live on this land, and how we can learn more about ourselves in our quest to not take away from the future.