Mouse control in a greenhouse

The plastic trap in a mouse runwayThis time of year controlling mice and the occasional mole or vole in the greenhouse is kinda like chess to me.  I’m not very good at chess mind you…  I’m too much of a rush in and get ‘er done kind of guy for chess.

In the greenhouse I have tried various rodent control measures.  The best one is our Border Terrier Watson…  but he’s not overly appreciative of the plants we are trying to grow in there - so he’s more the apocalyptic approach to rodent management - no rodents, no veggies left eitherer.

Because of his interest (and the chickens as well) in chowing on rodents, poison isn’t a favorite for me either…  although it usually does work pretty well the high humidity in the greenhouse makes it a challenge as it clump, glumps and smears all over.

So, a couple of years ago I learned about the concept of putting a simple old mousetrap in the runway you see in the picture (that worn path top to bottom) and let the mouse (critterer) that’s cruising along that path step on the trap.  It’s a great process - fast and effective…  but in the greenhouse with that high humidity I found the standard wooden traps were warping, molding and falling apart in a very short time frame.  That’s why I was so happy to discoverer these plastic versions of the mouse trap (see - you CAN build a better mouse trap!)  They work about the same as the old wooden ones but are easierer to load without smashing your finger tips and they don’t rot.  They just work.

Just cock the trap, set on a mouse runway and empty the bounty the next day.  Hey mice - check mate. 

Follow up: 2011 Pastured Chicken Season Statistics

There’s a follow up post on 2011 Pastured Chicken Season Statistics

It’s in response to a great question about managing feed waste.

Greenhouse inflator fan

Where the air hose brings air to the blower

Winter is one of those times around the farm where you discover those things you thought you did… but didn’t.  In the case of the greenhouse everything has been humming along just fine since last spring when we completed the construction…  the only thing I think we didn’t do was drill one small hole in the end to provide a fresh air supply to the inflator.

Our hoophouse / hightunnel / greenhouse hybrid is just that - a hybrid.  We designed the structure and bent the hoops ourself and don’t heat the structure…  but we also had to make things more robust than just a standard hoop house because of the stormy winds we get.  So, we opted to use a greenhouse inflator.

The inflator / blower

The inflator is a small fan that is supposed to draw air from outside the structure and inflate the space between 2 layers of plastic (like a ziplock bag).  The plastic is then taunt and the wind can’t grab and rip it off.  The added benefit of this kind of structure is the fact that the layer of air acts as a really good insulator helping to keep the passive solar heat the structure gains during the day from just disappearing so quickly at night.  The results have been great - when it’s 10F outside in the morning the inside of the hoop is still just above freezing.

So, back to the point here…  when we built the greenhouse I never put the inflator air source outside like I should have.  It worked fine (the structure isn’t exactly air tight) but it was pulling in very humid greenhouse air.  I don’t know if that would ultimately matter but I do know the installation instructions said to pull in fresh outside air to inflate the layers of plastic.  And who am I to not follow instructions?!

Where the fresh air comes in for the inflator

So with a 1 1/4” hole saw bit I poked a hole in the T-111 siding and mounted the inflator air source out there.  Who knows if it will ever matter…  but I guess NOW I can say “the greenhouse is done”!

Well, at least until I find something else that didn’t get finished.

Geothermal Heating - the costs

We changed over this fall and installed a geothermal system to replace our propane forced air heat to get away from the fossil fuel carousel that propane puts you on. (more like a roller coaster with the price fluctuations)
Here’s the complete picture of what we did for geothermal. Usually people who share this miss sharing the cost, which is the most frightening aspect… at first.  We thought it makes more sense to show you exactly how we calculated a ROI (return on investment) for geothermal and why it was the right choice for us. (to hear the full story of what went into this decision check out Coopcast #5)

First off, I can tell you we LOVE the geothermal system. Our hot water cost is offset by the “excess” heat from the geo compressor… we have a grill, stove, fireplace and then the balance of hot water off the propane tank and from Oct to early January our propane fill was only 90 gallons… and that INCLUDES the “shrink” you get in the tank volume with the much colder ground in winter.

The heat from geothermal is super even, the electric bills are FRACTIONAL over the old propane bills, it’s just great. Only “complaint” is the blower itself is louder because these units move more air than conventional furnaces - but that’s trivial, really.  Something we got used to pretty quickly.

The hardest part has been the ongoing installation - the company we went with were not very good so they have been out over and over and over and over… small things - but things I should not have “found”.  At this point I have learned so much about what NOT to do by the installers that I have half considered starting my own geothermal company to do installations…

The best part was the cost (really) - basically the system cost $25K (4 ton unit + field loops dug and backfilled + everything inside)… but before you freak out (like we initially did - look at the math).
In 2011 (don’t know if it’s still around in 2012) - there’s a 30% fed tax credit, so that’s $8K coming back. We are in NY so there were no state credits or rebates - but other states have them.
When we bought the system NYSERDA (NY’s energy research people) had a GREAT loan program in place it just made sense.

Here’s the math:
We took out a GE Capital 0% for 12 month bridge loan to cover the $8K we know we are getting back in the form of the tax credit - no cost of the money and for 4 months we just have to make on time payments of $201… not a big deal. Taxes get field, credit gets applied, we pay off the GE bridge loan. Done there in another 2-3 months.  Gotta love free money! (that means no cost to borrowing).

That left $17K to deal with. That’s where the low, low rate NYSERDA loan came in - 10 year term… payments ended up at $177 / month. We are paying extra principal on each payment (so total payment is $225). There’s a reason for that I’m getting to…
When we put all the numbers together in terms of propane costs - we knew we were paying about $225 / month for propane over the course of the each year - with propane at $2.29/gallon - and the math worked out that the geothermal unit, at that price, gets paid off in under 7 years with payments at that amount. (the recent propane fill was an insane $2.94 / gallon making us way ahead of the ROI curve of 7 years)
Bottom line - we pay $225 a month for 7 years - which is the SAME as locking in the $2.29/gal propane price - which is unrealistic - and after 7 years it’s only the cost of the electricity.
So far - the unit seems to add all of $50 / month to our electric bills.

I share all the numbers so people who are looking into this can see (at least in 2011) it’s a doable endeavor in terms of “normal people finance”.

Here’s the summary of payments:
We had $3000 “in the bank” for our annual propane pre-buy… So here’s how it gets used to kick off this project:
First 4 months of the bridge loan = $201/month (then tax return pays this off with Fed credit)
7 years - each month $225 / month (pays off unit + install in 7 years at a propane rate = 2.29/gallon)
Unit operating costs (about $50-$70/month).

So for 4 months we are paying about $500 / month to cover all the loans and the electric bill on the geothermal… and that comes out of that $3000 we had for our propane pre-buy.  Then, after the taxes come back and we pay off the bridge loan, payments drop to $225 a month for the loan and $50-60 a month (worst case) to operate the unit.  After 7 years, we are paying only $50-60 a month for heating and cooling because the loan is paid off…  and maybe another $200 a year for any extra propane we use for cooking, etc.

The life expectancy of a geothermal unit is in the neighborhood of about 25 years.  Also, it used to be very expensive to have maintenance on these units but in our area there are about 4 different HVAC companies that can service them, so honestly, the upkeep cost is about the same as the old furnace.

Think this might be for you… Well, attached to this post is a handy dandy spreadsheet (Excel format) that you can plug YOUR numbers into and see what the math looks like.

Geothermal Finance Worksheet

Electric "Snow" Fence

Planning is always important…  until you miss something, then, it’s pointless.  When we set up the winter pasture for the pigs this fall we made sure we put large a couple of large round bales of hay between their hut and the west winds we get.  We also put the feeder and the waterer where they would have minimal drifting to contend with.  The water bucket is also close enough to the barn that we can run a heavy gauge extension cord out to it for the heater to keep the water from freezing.  Really, it’s been a good layout.  Until we got our first real snows and strong winds.

Then, the snow that comes tumbling up the field blew against a pair of big round bales at the west end of the greenhouse (and around the greenhouse).  The result was a bunch of that air dropping the snow before it accelerated around the structure.  It dropped it on a section of our electric fence.

The issue here is really two fold.  First, snow drifts are packed densely and therefore they pull on the twine.  It’s not an ideal scenario by any stretch.  The second issue is when the fence is covered the pigs don’t see a barrier.  The result is likely pigs that think they can walk up the drift instead wallowing THROUGH the drift and hitting a hot wire.  Since they can’t “see” what’s getting them it’s anybodies guess if they would run forward or backward.  Another less than desirable scenario.

The work was easy with a plastic shove…  just dig it out and the pigs respected it.  The only thing I’m left thinking is…  if a 2’ drift can from from 4” of wind blown snow…  what’s this gonna be like when we have out first REAL snowstorm this winter?