Friday, February 24, 2017


Scott L. Price, P.E.
Electrical Engineering/IT Manager
Hunt Utilities Group LLC
Pine River, MN (218) 587-5001
MN Electrical Licenses: Master #AM08525 Power Limited #PL11071

Thursday, December 8, 2011

Copper Wire Testing Leads to Fun

The guys were doing some testing on copper wire and decided that the best way to see their test in action was to create a Jacob's Ladder. Who doesn't love these things? Paul quipped that every lab should have one of these on at all times, just as a matter of principle. At 12,000 volts, the arc was doing its thing happily.

After the tests were completed, you could visibly see the copper dust residue on the inside of the jar. The arc took the copper wire and, in the most scientific terms possible, made it go "poof" in a show of plasma and heat. Sounds fun, right?!

Friday, November 18, 2011

AC Use in Winter

The Mani Shop was built to retain the heat from the sun in all weather. On hot days or cold it has become apparent that the building design sometimes works too well. People with offices in the center of the building are often times sweating in the dead of winter.
This summer, a water based AC unit was installed to help with this problem. It works wonderfully. However, now that winter is here, an AC unit that relies on ground water will not cut it. So, identifying resources on hand, Mike and Ryan decided that cool air from the outside works just as well as cool water.
Therefore, our resilient team simply cut an insulated opening in an outside wall and connected home made ducts throughout the building. This will bring the cool air into the overheating rooms inside while maintaining the building's initial design feature.

Here you can see that Mike has all his ducts in a row.

Installation has begun.

You can see the opening from the outside here.

Tuesday, October 4, 2011

Solar Shade: Preparation for the Collage of Sustainability

In preparation for the Collage of Sustainability (the largest event to take place at the HUG campus), our team has had to make some changes to the atrium. With 150 visitors expected to participate, the atrium was designated the only place large enough hold all of them.

The atrium was initially designed to be a greenhouse, and with the south facing wall made up entirely of heat absorbing windows, it would become too hot for participants to bear. So, a solution was needed before the event began.

We decided that hanging a large piece of black cloth across the south facing windows was the solution we needed. (Some people call this contraption a "curtain.") However, it was decided, that this curtain needed to be done in style.

So, Wayne designed a little motor that would run up and down the metal posts set aside at each end of the cloth. This little motor would roll up the cloth and let more light in. If it gets too hot, the little motor runs down the metal posts and takes the black cloth down with it, creating more shade and blocking out the sunlight.

Here, you can see the little guy working.

Looking out from the inside, you can tell the difference the cloth makes.

Wednesday, August 3, 2011

A day in the shop

It's been a long time since I posted an update, so I thought I would post a bunch of pictures about what is going on in the shop today.

First is some control circuitry for the LEnR experiment. The schematic was drawn on the board.

Then, Paul works on the little circuit boards that will hold the circuits. He tries drilling the mounting holes...

But ends up making a very square looking owl face, instead.

But it's OK, because the owl fits in the test rack.

Then he commences the actual circuit assembly.

In another part of the shop, Jake and Jim C are working on a sink for the new garden shed that they will be able to wash plants and vegetables in.

On another table is a replacement water cooling coil that arrived damaged, so we had to get another one coming rather than installing it as planned.

An our resident wizard, Wayne, is busy refining the designs for the new duplex arc, even as the carpenters are building the foundation.

And Jeff is using the CNC router table to cut a bunch of holes into OSB pieces that will hold the under floor sensor conduits in the new duplex ARC.

And just outside the back of the shop, Mark and Dan are spending the day whipping up a replacement outhouse. Normally, we'd prefer a sawdust toilet in properties like the one this is for, but in this case, the usage is so light and the outhouse tank is already in place, that it makes sense.

And, while not being directly a shop project, the sign that Lisa had revamped and gotten installed Friday, got a landscaping make over with a mowing, a wood chip walkway and even some flowers with automatic drip irrigation. It is now very inviting as well as informational.

Self explanatory:

Also sort of self explanatory (especially after ninja attack):

Tuesday, July 5, 2011

Conditioned Air? Yes Please!

The Mani Shop has gotten a little bit cooler recently. With RREAL's expansion last fall, we rearranged the HUG offices in the building. This rearrangement made the greenhouse the main hallway and we found that in the summer heat this made the attached offices extremely uncomfortable. With a large area to cool and high costs of operating a concern, a normal air conditioning unit would not meet the needs of the shop. So, a new air conditioner was designed.

Using a furnace blower as the core, we designed the unit to work with cold water instead of a compressor. Using a radiator coil we inherited from an old grocery store, we are able to transfer the cold via an air exchanger to the blower at a rate of 2.5 gallons per second. We get a second use out of the water, too. We divert the water after it's used to help in watering the living garden on the roof via a sprinkler system. Plus, any additional overflow goes to the pond in front of the Mani Shop.

Here you can see Ryan installing the holes for the duct work.

It also recirculates the air it uses. This lets the unit work less often and keeps the air in the building colder, longer. This is very useful because the AC unity can push up to 2000 cubic feet of air per minute. This recirculation cleans the air and with an activated charcoal filter, it helps keep the air fresh by absorbing odors.

It was given a wooden bracket for a brace and was placed in the mezzanine level for easy access and maintenance.

Here you can see the air ducts and water hose.

The system is working wonderfully, now. In fact, on Friday we had several little girls splashing through the sprinkler system on the roof. Sounds like we got it online just in time.

Friday, July 1, 2011

Solar Conveyor

I am trying out a new way to bring solar heat inside, without using air or water as a medium. From a web search, it doesn't seem like anyone is trying this, except someone patented a solar belt collector way back in 1975!

Here is the inside belt. There are no fans. The belt heats the building through radiation and natural convection.

The powered conveyor roller only consumes 5W, and since the belt gives off almost 500W of heat, the coefficient of performance is almost 100.

The same belt extends outside where it absorbs the sun's energy. The glazing is inexpensive 6mm twin-wall polycarbonate. The belt is made from an EPDM pond liner. It is not as black as it could be, so the overall efficiency of the system is about 40-50%.