Thursday Morning … Heading Towards Lunch …

Things spin, they twirl, but generally they go by.

… In a straight line … or on some sort of arc … they go on.

I sort of meander … bumble might be a better word … but I notice.

Small things mostly … they grab my attention.

And today … Something new.

These things as they spin … sometimes bump … sometimes collide.

The evidence is everywhere. One rarely sees it happen, and perhaps rarer still … notices.

Not today … though it happened over a year ago.

Let me try to show you …

A Russian Ballerina, years in the making … but far from home.

The Urban Nutcracker, here in Boston …( a collision I did not see.)

A school “field trip” … perhaps you know the sort.

Duke Ellington … Billy Strayhorn …

Dance of the Sugar Plum Fairy …

Someone elses tutu.

All aligned … all moving … all …

Unaware …

Lights out …

A cue …

Lights up … and press play …

A drum beat played long ago … revisits.

She starts her dance … Two saxes join in.

The drums and her dance.

More horns and she dances …

They begin to notice.

Then … something unexpected …

They clap along!!!

More horns … and she dances.

She does not hear them … yet …

Then … POW! … It hits her. She hears them and she knows.

Must dance … Must finish this dance … The look … for a split instance … across her face.

And dance?

Does she ever … They get louder … it drives through her.

More saxes …

then horns …

then …

Gone …

Things spinning … some twirling … on and on … to no ideawhere.

Do they remember?

Will she forget?

How long before her feet really felt the ground?

Can you hear them?

Did you see that?

And …

I …

meander on …

… Not just the loud parts!

The 2014 Pet Rock Festival … Second stage “tech world”

The generator had the day off ... The system ran for 5 hours and 15 minutes, used 1.7 kWh of power ... Only using 24% of the 550 amp hour battery!

The generator had the day off … The system ran for 5 hours and 15 minutes, produced 1.7 kWh of power … And only used 24% of the 550 amp hour battery!

When you replace the “traditional” gasoline or diesel generator with battery power some really neat things happen.

The first thing you might notice is that there is no noise.

And with no generator running in the background there are no exhaust fumes, no heat or extra cans of fuel to worry about. That means the batteries can be placed almost anywhere, eliminating the need for the long extension cords, cable ramps, tape … and the time normally involved with getting power where you need it!

Great seats!  ... They probably do not know they are sitting next to the "generator"!

Great seats! … They probably do not know they are sitting next to the “generator”!

With a properly sized battery system … there is no need to refuel … No flammable liquids … or downtime.

The batteries can be set up and used anytime, anywhere and theoretically can be sized to do almost anything.

Anything? … Well … Almost anything … Fairbanks is pretty small as far as cities go!

Fairbanks, Alaska has the world’s largest rechargeable battery (according to Wikipedia as of 6/17/14).

From the Golden Valley Electrical Association web site …

“Completed in December of 2003, the BESS (Battery Energy Storage System) can provide 27 megawatts of power for 15 minutes in the event of a generation or transmission related power outage.”

“The BESS responded to 60 events in 2013 … Preventing a total of 310,492 member outages … That’s an average of over 5,000 customers per outage!”

Their battery system was sized for the job … And from what I have read … Does the job very well.

My 12 volt systems are quite a bit smaller … My largest, a 1050 amp hour system is roughly the equivalent of a 6,000 – 8,000 watt generator … My smallest, a 276 amp hour system is roughly the equivalent of a 1,500 – 2,000 watt generator.

Perfect for a lot of small events and festivals!

When you use a battery system, power is removed from the batteries only as it is needed, with the rest of the stored power staying in the batteries … To be used as it is needed.

With a generator, electricity is produced at a constant rate and you use what you need … With any extra power /electricity from the generator being wasted.

With a battery system the louder things need to be … the faster the power is removed from the batteries … The loudest “peaks” of a performance draw the most power …  The spaces in between those peaks draw a lot less power from the batteries … With the quiet parts in between the notes drawing almost nothing at all … extending the running time of the system for the event.

Music with a wide dynamic range gets a double benefit when switching to a solar charged battery power source … Aside from being “clean and green” … The overall dynamic range is greatly improved by removing the “noise floor” created by even the quietest of generators.

You will be pleasantly surprised to hear even the quietest sections of the performance … Not just the loud parts!

Enjoying the sounds of the Boston Pops Brass Ensemble in beautiful Franklin Park, 6/24/2012

Enjoying the sounds of the Boston Pops Brass Ensemble in beautiful Franklin Park, 6/24/2012

Easter Sunrise Service, Castle Island, Boston.

In the mean time …

Easter sunrise service on Castle Island in South Boston …Wow!

The view to the east is amazing. I am not going to try to describe it, but it is worth getting up early for … At least once!

I had been providing the sound system for the event for a couple of years and had really enjoyed setting up the sound gear in the dark and watching the new day arrive.

Easter morning view from Castle Island

The airplanes are not landing at Logan airport across the harbor at 4:00 in the morning and you can actually hear the harbor, the sound of the waves hitting the shore, some large ships going by … Add the flash of light from Boston Light and the slightest hint of change out on the horizon … It is very nice!

This year I had asked my contact with the Castle Island Association if I could try powering the event with one of my solar powered battery rigs and he said yes!

Normally … By the time most of the people arrive for the Church service the generator is already running with its constant drone covering up everything but the “red eye” flights coming in and the occasional overhead sea gull.

This year the first sound breaking the harbor “soundtrack” was the “Good Morning” from the priest celebrating the Mass … I’m sorry if it startled anyone!

The system ran for 2.5 hours and used .35 kWh of power … a tiny amount by any standard. Basically the “idling” current draw from having the four wireless microphones,  mix rack and amplifier on … With no background noise to compete with, the overall sound level did not need much power to cover the audience standing an an area almost the size of a football field.

The small “solar system” I brought to power the event was about the same size and weight as the generator that I helped off load from the park rangers utility tractor in previous years. Something else to think about … Eventually!

But back to rewiring …

The battery systems had worked wonderfully at powering the events so far. But I had unknowingly been getting a little help from good old fashioned “dumb luck”.

If this project was to get out of the tinkering stage I wanted to do it without needing that help.

Adding the battery meters was going to provide some very useful information, adding fuses was going to keep everything and everyone safe … and spending a little “quality time” with my coffee pot and calculator was going to get the systems performing as well as they could … For a long long time!

To find out how long you will have to check back later … Hopefully much later!

In working with 12 volt DC power it is very important to size everything for what you are trying to do … In my case … Powering all the equipment needed for an outdoor concert.

Sizing the wire used and laying out the equipment so that as little power as possible is lost to resistance in the wiring of the system … Ideally keeping the loss between the batteries and the inverter to less than 1%

To do that I needed to use the largest, shortest wires possible.

Using a voltage drop calculator like the one found in  “”  you can see what size wire you will need to use. For this part of the project I used short (18″) #2 cables to go from each of the batteries to a pair of insulated buss bars, and total of about 8′ of #2/0 cable to get from the buss bars, through a circuit breaker, fuse and shunt to the inverter and back again.

If I’m doing my math correctly I am only losing .1463 volts (1.17%) to voltage drop with a 200 amp, 12.5 volt DC load … A little more power than what you could get from a standard household 20 amp circuit.

It sounds like an awfully small amount of loss to get excited about, until you realize almost everything in a 12 volt system will shut down when the voltage drops below 10.5 volts. Losing .1463 volts from 12 volts does not seem like much … But if you only get to “play” with the 2.4 volts between 12.9 volts (a full battery “at rest”) and the 10.5 volt “shut off point” … Losing that .1463 volts means I would lose between 5 and 8% of my total power at full current … And if I wanted to keep the batteries alive as long as possible I do not want to discharge them fully … I could be losing over 10% of my power … to wire!


I am hoping to give you a little “photo” tour of how I wired one of the systems in my next post.

Luck of the “Irish”!

In the mean time … The show must go on … The rewiring project was going to have to wait.

3/17/2013 … If you live in Boston that date can only mean one thing …

The South Boston St. Patricks Day Parade … Where being Irish is not really required!

I got a call from Mike Majorowski wondering if my battery system would be able to power a float for his band in the parade.


To see if it could be done I set him up with a couple of “Kill-A-Watt meters to use at his next gig to see how much power they would need … While I started to worry about the weather. Rumor has it that batteries do not like the cold!

With the readings he got from the “Kill-A-Watt meters It looked like my smaller battery system would do the job … At least if the weather co-operated and we got that perfect 77 degree day the batteries were rated for (this is Boston … and I’ve shoveled snow in May!)

I explained my “concerns” to Mike and we decided to try the parade using my larger system … At the smaller system’s price.

We had a beautiful sunny day for the parade … If you don’t mind a little cold wind … We started sound check at 10:00 am at 28 degrees And got all the way up to a “balmy” 37 degrees somewhere along the parade route!

Five hours of run time, 1.83 kWh of power used … We even got a nice “Cool!” From the Boston Police Truck team inspecting all the floats when they asked where we were getting our power from … apparently we did not need a special permit for using a generator on the float … Cool indeed!

At the end of the day the inverter battery meters still showed 90 – 100% full … It would have been nice to have the new meters installed … The parts had arrived … the extra time needed to install them was still on back order!

It was my first event moving the battery boxes around by myself and one thing was certain … Those battery boxes are heavy … Very heavy!

The larger battery system with the Trimetric 2025 meters installed

The larger battery system with the Trimetric 2025 meters installed

The larger system consists of a pair of “Site Safe” tool boxes with each box weighing in at about 500 pounds! … So “portable” is a relative term!

Moving them from the truck to a loading dock, or in this case … To the back of the “roll off” tow truck that was used for the float was pretty easy … Pushing them up the ramp to my truck? … Not so much!

Moving them around was going to take three or four people … Or a lift gate on the back of the truck … I will need to figure that one out later …

My to do list keeps growing!

Back to the drawing board!

Oh well … It turns out almost everything I did on my first attempt at going solar was wrong.

Wrong wire sizes, wrong lengths, wrong assumptions about how a bank of batteries should be wired … All of which made for a lot of possible failures.

Overestimating how much power I would actually be using … And more than a little good luck keeping any of those failures from happening!

So … Back to the drawing board …

The first “order of business” was to get a real metering system installed … It was time to find out what was really going on with the batteries.

I needed a “gas gauge” I could trust.

The Trimetric meters from Bogart Engineering are highly recommended by a lot of folks. … I decided to try the 2025 RV model for the project.

The 2025 is a very neat device that keeps track of the power in Amps  going in to and out of the batteries … A quick look will tell you the voltage. Press a button and you will see how much power is going into or out of the batteries. Press the button again and the meter will tell you the batteries are 87% full (… Or 18% full … It might be time to start thinking about worrying … Soon!).

In any case … More information than I could have hoped for!

The folks from Bogart Engineering have designed the meters to do a lot more … But those three things were going to answer a lot of my questions … And keep me out of trouble … For a little while at least!

Adding the meters to my “rigs” was going to take some rewiring … and some math … More on that later.

Since I was going to have to get in and do some rewiring to install the meters it made sense to go in and fix as many of my wiring mistakes as possible … My good luck was only going to get me so far!

If  you’ve been following along since the beginning you may remember my first big battery powered show having some yellow “warning” LEDs flashing on one of the inverters. The band had not gotten any louder … But something had changed … It took over a year to figure out what had happened … the power in the batteries was not getting to the inverter.

Resistance was “robbing” the system of power.

The wire I was using was too small and too long for the current that was trying to get from the batteries to the inverter … Causing a voltage drop … Causing the inverter to “ask for more power from the batteries … Causing the resistance to go up …causing more voltage drop … Causing …

It was a good thing I pulled the amplifier from one inverter and plugged it into the other inverter when I did … Or that show might have been the last!

My common sense approach was not helping at all … Luck … On the other hand … Was!

When using batteries to power something you do not want to waste anything. Leaving a 60 watt light bulb on overnight will “eat up” a lot of your battery reserve. It can be done … You just need more batteries … And solar panels to make it happen.

A little common sense would tell you … If you do not need it … Turn it off!

Common sense probably won’t tell you how much power will be wasted by using the wrong wire. Too small or too long of a wire could waste as much power as that 60 watt light bulb.

When using DC power a good “rule of thumb” is always use the largest, shortest wire you can.

So … I bought a bunch of larger wire to replace the stuff I had started the project with, ordered some meters, shunts, heavy duty buss bars, fuse blocks, fuses, lugs, heat shrink tubing … and my new favorite tool … A hand held crimper capable of hand crimping up to # 4/0 cable!

I wanted my systems to perform as well as they could … The solar powered equivalent of a finely tuned sports car as it were.

I’m afraid I’m going to be  seeing lots of 4/0 in the near future …

January, 2013 … and the Flu!

January, 2013, a book to read, some questions to answer … And the flu!

“Armed” with my trusty old iBook G4 and the second last dial up internet connection on the planet …  it was time to try “Googling”again!

(I really hope I am not that last person still on “dial up”)

It turns out there is some very good information out there … Mostly hidden in between some small scale items used to charge your cell phone or iPod … and some amazing systems even I find too incredibly good to be true … But perhaps … I’m still learning here!

Searching for solar power will overwhelm you … Narrowing the search down a bit to solar powered sound will get you a lot of neat things to play your iPod on, an interesting sound art project … And if you look far enough you will find …

Some nice photos of a couple of portable solar power systems being used at events … But I was not able to find out more.

A lot more searching, will get you to the North Texas Renewable Energy Group’s “Solar Shuttle” … A very impressive silent portable power generator … That happens to be solar powered … Wow!

They keep redesigning their web site … So you may have to look a bit.

This morning (8/25/2014) I found it in the “member projects” page under “The Solar Shuttle solar trailer” link.

Make sure you check out the link to the “PDF photo journal”

Wonderful stuff to find, but no help with finding any answers to my questions.

… Until Steve Gagnon sent me a link to Handy Bob Solar!

Thank you Steve! … And Bob!

Bob has been “boondocking” … living off the grid … for years … And had to try a lot of things to get a solar power system to work on his RV.

Check out his blog … But start a fresh pot of coffee and get comfortable first … He has a lot to share with anyone willing to take the time. And if you are interested in off grid solar power … find the time. What “Handy Bob” has to say is worth it!

A lot of why someone boondocks gets lost as soon as you start up a generator … The peace and quiet of the wide open spaces is easily overwhelmed by even the quietest of internal combustion engines.

Bob seems to have his feet firmly on the ground of common sense … And what he was running into trying to set up a working solar power rig for his RV did not seem to follow what his common sense was telling him … It should work … The question was why didn’t it.

Backwards from my questions by about 180 degrees … It shouldn’t work … So why is it?

My problem was that I was overestimating what was going on … Leaving me with extra power at the end of the day … In the RV world … It seems that underestimating what was going on was leaving a lot of people with not enough power at the end of the day.

I have the easier problem to solve.

I have learned a lot … And will continue to learn  from Bob and the other folks out there who have taken the time (and spent the money) figuring out how to make off grid solar work.

Thank you all for sharing!

Now to put some of those lessons to work!

When in doubt … “Google” it!

I obviously needed to learn more about things … But how?

When in doubt … “Google it”!

Hmmmm …. Well … It was worth a try!

I’m not very tech savey … (Said as I sit here writing a blog on an I-pad!)

Getting around on the internet and finding what I was looking for has been a hit or miss proposition for me.

And having a smart phone that does not like me does not help things

… But I digress ….

My first attempts at learning about solar power and batteries on the web did not get me very far.

However … The folks at Boats and Motors sold me a wonderful book about how an electrical system works on a small boat!

The 12 Volt Bible by Miner Brotherton and revised by Edwin Sherman, full of lots of great information about DC power and batteries … And the occasional mathematical formula for us math fans out there (out there … A pretty good way to describe …)

Originally written in 1985 and revised in 2003 … It turned out to be a great place to start.

The boating world is a really good place to find both hardware and information … It is one of those places where being a little wrong can get you into a lot of trouble. The kind of reliability needed in the boating world is what I wanted / needed for this project.

In the entertainment world … failure is not an option!

The help I received from Boats and Motors and West Marine was wonderful … they were very happy to share what they knew and if they did not know, would try to find out … And if they were not able to come up with an answer, would apologize for not being able to help!

I really like these folks!

So lots of questions and a book to read for when things with the “day job” slowed down.

I had a busy fall into New Years season ahead of me and nine months until my next booked solar powered gig … So I “moth balled” everything … With a somewhat regular schedule of “top off” recharging to keep the batteries from an early death (I did get far enough into the 12 Volt Bible to learn that much).

Made it through the year … With what had become a wonderful tradition of ending the old year mixing the Concert for Peace at St. John the Divine in New York … And the quiet drive back the next day.

If you ever get the chance to … Go!  … It is an amazing event!

2012 had been a good year … Some amazing shows …  It was great to be involved with the Urban Nutcracker again … and everything about the solar project had been a lot of fun … My dad and I working, almost non stop to be ready for that first solar powered Elma Lewis Playhouse in the Park “gig” … a 2:00 in the morning close encounter with a skunk kept things interesting!

I was truly amazed at what the batteries were able to do.

At a street fair in Andover I  “caught” one of the crew from the main stage down on his hands and knees looking to see if I had a power cord coming up from the manhole cover I had “parked” one of the battery boxes on top of.

Apparently I was not the only one being amazed!

11 events running over 42 hours … without running out of power … I was able to record 19.03 kWh of power used … It took a while to realize this was going to work and I should be taking notes … I missed three of the early shows.

Photos would have been nice too!

In any case … January was looking promising for figuring things out … A couple of quiet weeks … and the flu.