Freezers up and running

SUBHEAD: Our two new freezers (one converted to fridge) are running off solar and working as expected.

By Juan Wilson on 1 September 2018 for Island Breath -
(http://islandbreath.blogspot.com/2018/09/freezers-up-and-running.html)


Image above: Top opening 10.6cuft General Electric chest freezer model number FCM11PHBWW with three movable bins and built in light costing about $449 on our lanai.

We are off the electric grid (KIUC) and run our homestead entirely on photovoltaic power spread across seven dedicated systems. One is dedicated to just our freezer and refrigerator. For quite some time we have suffered with inadequate energy to run our 16cuft refrigerator.

The small chest 4.5cuft freezer has been no trouble, but the refrigerator has been a real hassle - especially in the darker winter months.  Add to that our eight 405 amp-hour 6volt batteries dedicated to cooling food are going into their fifth year.

We realized that the chest design of the freezer was a great advantage over the front loading fridge. Every time the fridge door is opened all the cold air slides out. If you are making a complicated meal it's tough keeping that fridge cool.

We replaced a front loading 16cuft refrigerator and a 4.5cuft freezer with two 10.6cuft freezers. One of the freezer we put on our covered lanai just outside of our kitchen/dining room. It is more out of the weather than our previous freezer location that was in our carport (shop/laundry room).

The other freezer was placed where our upright front loading refrigerator used to be. Note we never got the use of the jalousie window with the old fridge there.


Image above: Top opening 10.6cuft General Electric chest freezer converted to a fridge with the use of a thermostat to shut it off when the temperature approaches 32ºF

Of course, there are advantages in organizing (or the lack there of) when using an upright refrigerator. Fortunately the freezer we found to use as a fridge had two features that helped a lot.

One - it comes with three plastic coated metal wire bins that slide on a ledge just under the top .
Two - it has a light on the underside of the top opening door that turns on when you lift the top.




Image above:Above the thermostat and monitor for the converted freezer to make it a refrigerator.

Left is the control for the thermostat that has a sensor on a long copper tube. It can be adjusted down to 20ºf. We are using it set to 32ºf. On the right is the source of electricity. The tan extension cord runs down and through the wall to the covered porch outside our front door. That is where our 110volt inverter sits just over the battery array under the porch.

Plugged into the cord is a power monitor that shows the refrigerator is pulling 88 watts while it is cooling. Plugged into the monitor is the thermostat and plugged into the thermostat is the fridge.

We bought the Johnson Controls Freezer Temperature Controller from Amazon.  This thermostat converts the freezer to a fridge.

So far so good. We are watching and adjusting how we load and use these units. 

See also:
Ea O Ka Aina: The Forthcoming freezers 8/25/18
Ea O Ka Aina: Convert Freezer to Fridge 7/21/18
Ea O Ka Aina: Guilt Free Cold Beer 3/7/10





.

The Forthcoming Freezers

SUBHEAD: Our ability to refrigerate and freeze food reliably off-grid requires converting to chest units only.

By Juan Wilson on 25 August 2018 for Island Breath -
(http://islandbreath.blogspot.com/2018/08/the-forthcoming-freezers.html)


Image above: Our current 16cuft fridge next the front door. The new 10.6 cuft freezer will turned be transformed into a refrigerator (set at 33 fahrenheit with a GE thermostatic switch. Note the microwave on top of the fridge is used only for storing open bags of chips and crackers. It's not plugged in because it will trip the PV inverter if turned on. Photo by Juan Wilson.

[IB Publisher's note: We are facing a problem with our 16 cubic foot refrigerator - it's not efficient enough to run on the the batteries charged by our solar PV system. We are looking to convert a 10 cubic foot freezer into a refrigeration unit and live with the inconvenience of organizing and searching the bin for its contents. We'll let you know how that goes.]

We have been off the power grid long enough to have learned a few things. Perhaps the toughest lesson was finding it really difficult to keep refrigeration going 24/7/365. A lot of things that require power can be episodic. That includes wi-fi internet access, electric lighting, and entertainment systems.

We have moved up from 8 120 amp-hour 12 volt deep cycle marine batteries to 8 405 amp-hour 6 volt AGM batteries. That's the same size array of batteries that run all out power outlets and switched lighting. After struggling through several seasons of darker than summer days we realized we could not run conventional refrigeration. That being an upright unit with a front door. The unit simply loses most of its cold air every time you open the door merely to see what's inside.

We had to go to a chest refrigerator. We also needed a bigger freezer to store all the food we process and store (like a year's worth of macadamia nuts, and packages of pre-cooked and seasoned cassava, taro and breadfruit.

We read about this solution in Kendra's post "Convert Freezer into Fridge" (http://islandbreath.blogspot.com/2018/07/convert-freezer-into-fridge.html), from New Life on a Homestead on 7/21/18.

Since July we have taken steps to rid ourselves of and upright refrigerator and expand our capacity to freeze for for long term storage.  The plan included purchasing two 10.6 cubic foot freezers. One would be converted to a refrigerator using the technique in the referenced article linked above.  The other would be a straight up freezer.

We purchased the freezers from Home Depot.  They are General Electric model FCM11PH Chest Freezer (garage ready) with an Energy Guide estimate of $26 estimated yearly energy cost. Of course that $26 is totally unrelated to the actual energy cost from Kauai's KIUC power company opr the fact that we will be running them off batteries charged from solar panels.

What the $26 does indicate is that this freezer is in a sweet spot being less energy costly than any of the smaller freezers we considered. Of course, we'll see what find out the actual consumption only when we are up and running.

We were notified yesterday that the two freezers had arrived on Kauai and would be delivered on August 31. So we are beginning now to execute changes we'll need to accommodate the switch over. Will have Home Depot remove the 4 cubic foot freezer in our garage the 16 cubic foot refrigerator.

One of the new freezers (the one we'll user as a fridge) will be placed in our kitchen/dining area where the old fridge was. It will be wider, lower and a bit less deep and requires some storage changes - like no storage on top of the fridge like now.

The other freezer will be on our lanai, just outside the the kitchen/dining area. That means no more trecking down and outside to get to the garage and our current freezer.

More on the installation and use of these units as we go.

On re-reading the specs again I realized that these new freezers have built in lighting. That is great, in that I won't have to install additional lighting on each unit that would be foot operated (or something).

More on this effort when the freezers arrive.


Image above: Our current 4 cu ft freezer is closer to the weather than the lanai location we intend for its replacement. Note rust at front right corner closest to the outside of our open "garage" (washroom, shop, storeroom, etc). Photo by Juan Wilson.

Convert Freezer into Fridge

SUBHEAD: Solar power couldn't run the conventional fridge, but converting a bin freezer worked. 

By Kendra on 23 September 2014 for New Life on a Homestead -
(https://www.newlifeonahomestead.com/convert-chest-freezer-to-fridge-solar/)


Image above: A typical low cost small bin freezer. From original article.

[IB Publisher's note: We are facing the same problem with our 16 cubic foot refrigerator - it's not efficient enough to run on the the batteries charged by our solar PV system. We are looking to convert a 10 cubic foot freezer into a refrigeration unit and live with the inconvenience of organizing and searching the bin for its contents. We'll let you know how that goes.]

Why Would We Want a Chest Fridge?
\In the months before purchasing our solar kit, we took measurements of how much power each of our appliances pulls using a Kill A Watt Meter.

After plugging our fridge into the meter for several days, we were able to determine that our upright unit was pulling about 2.25 kWh/day. With a solar system that will only produce 4-6 kW/day (assuming sunny days and clear skies), we had to find a way to reduce the load our fridge required.

I did a lot of research online, reading solar forums to find out what other people were doing for refrigeration off the grid. Many people use propane or gas refrigerators, but we didn’t want to have to depend on buying fuels to keep a fridge running.

Some people recommend solar refrigerators, but with the smallest models starting out at around $700, this option was way out of our price range. A more primitive alternative is using a Zeer Pot, but we really need something more practical than that for our everyday needs.

And then I came across something that sounded too good to be true:

Converting a chest freezer… a regular ol’ chest freezer… into a super energy efficient fridge.

Surely it would be complicated. There would be re-wiring and all sorts of complicated electrical modifications. Right?

Actually, not at all. It’s as simple as an extra plug. But I’ll get to the technical stuff in a minute.

One of the best things about a chest fridge is that they require just a fraction of the energy an upright model uses. Think about it. Cold air sinks. So when you open an upright fridge, all of that cold air you’ve paid to produce falls right out of the fridge at your feet, which in turn causes it to run more often. But with a chest fridge that cold air just sinks back down into the unit, requiring less energy to keep it cool. That’s why grocery stores like to use chest fridges.

Even if you don’t have any plans for going off the grid, you might want to consider the benefits of replacing your upright fridge/freezer with chest units simply for the energy savings.

Switching to a chest fridge isn’t for everyone. There are definite drawbacks to a system like this, which we’ll talk about later. But for us, it was a perfect and affordable option to use alongside our solar kit.


Step One: Finding The Right Freezer
When shopping for a chest freezer to convert to a fridge, find the smallest unit to accommodate your needs. Generally, the smaller the freezer the less energy it will require.

We found a 6.8 cu. ft. Magic Chef freezer for $80 on Craigslist. It’ll fit an 8×13 casserole dish down in the bottom, so there’s plenty of room to store leftovers or make-ahead meals. Although this unit isn’t Energy Star rated, it was comparable. Before deciding on a purchase, do some research into how much energy it uses compared to other models of equal size.

The amount of watts it uses as a freezer will be different from what it’ll use once converted to a fridge, but by comparing models you can at least get an idea of whether it uses more energy than necessary or if it’s pretty energy efficient from the get-go.

To figure out how many watts a freezer pulls, you’ll need to use the formula: Amps x Volts = Watts.

There should be a plate or sticker somewhere on the freezer that tells you how many amps and volts your freezer uses.

Just for reference, our freezer breaks down like this:

2.0 Amps x 115 V = 230 Watts, or .23 kW (1 kW = 1000 Watts).

This tells us approximately how many watts the unit uses per hour.

After converting the freezer to a fridge, our unit was pulling .68 kWh/day. Once we loaded it up with food the chest fridge is now reading about .51 kWh/day. That’s less than a quarter of the energy our upright fridge used!

If you get a used chest freezer, make sure everything is in good working order, and
ask about the last time the freon was topped offscratch that, but do make sure there isn’t a leak in the line.

Step Two: Controlling The Temperature

Once you’ve found a chest freezer the next step is to convert it to a fridge. The easiest way to do that is to purchase a Johnson Controls Freezer Temperature Controller. We got ours for about $50 on Amazon.

With this device, there is no re-wiring or complicated configuring whatsoever. It’s as simple as a plug.

Here’s how it works…

Plug your freezer into the controller. Plug the controller into the wall outlet. Set the thermostat on the controller to a good temperature for refrigeration (we’ve got ours on 32*). Place the copper prong in the freezer, feeding the copper wire underneath the lid. The temperature in the box will raise to the new thermostat’s setting, and your unit will automatically go from being a freezer to a fridge. Easy enough?

We mounted the controller to the wall behind the chest fridge. You can see the copper wire leading into the fridge from the back side. It just slips right underneath the lid. My husband also mounted a power strip with timers for our chest fridge and freezer, so we can control how often they come on when our solar is low on power.

Here’s the inside of the fridge before it’s filled. You can see the copper wire and probe in the center of the fridge. We try to keep it hanging around the middle of the fridge to keep the temperature consistent. If the probe is closer to the top of the fridge, it may read warmer air causing the unit to cool down unnecessarily.

I try to keep the prong from touching the wall of the fridge. Not sure if that matters, but it seems like a good idea.

A refrigerator thermometer helps us make sure it’s staying at the right temperature.

Getting Used To A Chest Fridge

Once I had sufficiently emptied our upright fridge/freezer, I was ready to move what remained to the new solar powered chest fridge. I was shocked by how much space was being taken up in our fridge by stuff that didn’t even require refrigeration.

I’m still working my way through the condiments and canned goods (I had like six jellies open in the fridge… yikes!), but when it comes down to the basics, we really only need the fridge for dairy products, a few condiments, leftovers, and more delicate produce such as leafy greens.

Down in the bottom of the fridge I put a milk crate to hold condiments and things we don’t use that often. Over time, condensation builds up in the bottom of the fridge and it needs to be soaked up. Having all of the loose jars up out of the water and in one easy-to-remove container makes cleanup a little easier.

I’ve used two freezer baskets to take advantage of the space at the top of the fridge. In these I put the stuff we use most often. I’ve found that having our leftovers right on top where they can’t get lost has really helped me use them up, where as before they would often get pushed to the back of the fridge and forgotten.

Having two baskets is a good use of the space, but it isn’t as practical as I’d like. To get to anything below, we have to remove one of the baskets first. Ideally, we would just slide one basket to either side to reach the bottom.

Frugal Kiwi has an excellent post on Organizing Your Chest Refrigerator, in which she shares some fantastic ideas for making the most of your space while still allowing access to the bottom of the fridge. I’d love to make shelves like her husband made, eventually.

But what about a freezer?

Yes, we still have a freezer. Instead of having an upright fridge/freezer AND a chest freezer (which is what we had before), we’ve consolidated all of our frozen foods into the one chest freezer. The chest freezer by itself pulls about 1kWh/day, which we can support with the solar panels alongside the chest fridge.

Drawbacks
Yes, there are trade-offs when switching from an upright to a chest fridge. Here are a few I’ve discovered so far…

Convenience– Obviously, having to move stuff to reach down into the fridge is a little less convenient than we’re used to. But honestly, it really hasn’t been too much trouble.

Condensation– The fridge does accumulate water in the bottom from condensation. About once a week I pull everything out of the fridge and dry it up with a towel.

No Instant Filtered Water– With our upright fridge, the kids were used to helping themselves to cold, filtered water straight from the fridge door. Now they have to get water from the kitchen faucet, ’cause it’s too far down for them to reach into the bottom of the fridge. I’d like to get a Berkey or other beverage dispenser to fill with ice water to keep on the kitchen counter so that it’s easier for the children to fill their cups whenever they need to.

No Ice Maker– Of course, we don’t have an automatic ice maker now either, so it’s back to the old fashioned ice cube trays. Which works just fine.

Space– Having a chest fridge and a chest freezer definitely requires more floor space than an upright model. This may be a deal breaker for you. We have chosen to be unconventional (imagine that!) and move our chest fridge and freezer into the master bathroom, which is on the north side of the house and stays the coolest.

We had to sacrifice the garden tub, but honestly we probably wouldn’t have used it anymore anyways since we’ll have to be more conservative with our water usage. (Now I get to figure out the best way to fill the empty space where our fridge used to be in the kitchen.)
With a little adjusting it really hasn’t been difficult to get over these minor inconveniences. In our opinion, it has definitely been worth the trade.

Total Cost
The total setup cost to us was about $130 for a fridge that now runs on solar power, which we quickly made back by selling our upright fridge. Your cost will depend on the deal you can find on a chest freezer, plus about $50 for the thermostat controller.

Refrigerators generally don’t cost that much to run for a year, especially newer more efficient models. But when your power is limited and every watt adds up in a big way, converting a chest freezer to a fridge is a great way to significantly reduce your household energy load.
.

Guilt Free Cold Beer

SUBHEAD: Dedicated solar PV rig to refrigerate green beer in New Zealand. Learn how.

By Dave, Irena and Greg Lowe on 15 April 2009 in About Lowenz -
(http://www.lowenz.com/about-lowenz/projects/guilt-free-beer-fridge)

 
Image above: Two 175w solar PV panels  powers full size refrigerator. From original article.

In the average New Zealand home hot water heating is usually the single biggest user of electricity.

Surprisingly after hot water heating the next biggest usage is often old and inefficient fridges. This applies especially to old fridges which are often parked out in garages as a second or classic Kiwi “beer fridge”.

These usually have very poor and often partially missing door seals as well as inefficient insulation and compressors. Also in many cases the compressors still contain CFCs which are now banned as ozone depletion substances rather than modern non ozone depleting refrigerants.

We decided to look at this issue as a demonstration project for home solar electricity production by photovoltaic panels.

Our installation consists of two 175 watt Sharp photovoltaic panels coupled via a charge controller to two deep cycle 12 volt lead acid batteries. The charge controller is a Morningstar Sunsaver which uses maximum power point tracking to maximize the power output of the photovoltaic panel array.

This is done using an automatic tracking algorithm which tracks the array maximum power point voltage as it varies with weather conditions ensuring that maximum possible power is harvested from the array through the course of a day.

SunSaver MPPT Controller (right)

This type of controller can significantly increase the amount of power available from a given array and is a much cheaper option than adding extra photovoltaic panels when more energy is needed.

Case with deep cycle wet cell batteries

Energy is drawn from the batteries using a Latronics 800watt pure sine wave inverter which converts 24VDC from the batteries to 230V 50 Hz AC.

For our demonstration project we are using this energy to run the LOWENZ office (computer system and energy saver lights) and a high efficiency Gram fridge. The fridge is 220L with a rated energy consumption of only 0.34KWhr/day.

However our experience so far is that it is using much less energy than this, only about 0.25KWhr/day, because we are testing the system as a “garage beer fridge” literally in our garage where the ambient temperature is much cooler than inside a house.

Clearly the power consumption of a fridge will be a direct function of the difference between the exterior and interior temperatures so it would use more energy if it was run inside a house where the temperatures are warmer.

And yes our fridge does have beer and wine stored in it so this is a very practical demonstration.

Fridge full of cold beer

So far we have only run the system over a two month period in winter when sun angles are much lower (only 28º above the horizon) in Wellington at midday on the winter solstice.

However despite this we have found that the system produces just over 1 KWhr/day on sunny days which is more than enough energy to run the fridge and the LOWENZ office and we have used the surplus energy to cook meals over the course of several hours in a 160 Watt slow cooker or to run lights.

The Wellington weather over May and June 2009 has been pretty shocking with a lot of very cold dull southerly days.

However, even during these conditions, the system has still generated enough power to run the fridge and office computer although we have had to conserve on extra lights.

Its important to note that because this system is not connected to the grid it is not subject to local power failures and will be capable of supplying emergency power if mains power is lost through an Earthquake disaster for example.

This has been a fun project, and in hindsight very simple to put together. If you are interested in something like this for your home please contact us for details.
.