Category: energy

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energy house

The Energy Efficiency Project: Month 3

energy efficiency project month 3

February 12th – March 11th, 28 days

This month we continued to paint and started building some bookshelves.  We also hosted a first birthday party and started getting ready for our upcoming outdoor projects. We were splitting our time between the house and our apartment in the city during this month, so the house was using minimal maintenance energy while we weren’t in it. For example, the furnace was set just high enough to keep our pipes from freezing while out of the house, and really only the fridge was using electricity most of the time. So this month won’t be the best representation of our energy use, but will hopefully serve as a good reminder to put your house into low-energy-use mode when you’re gone for extended periods of time. As far as energy efficiency initiatives went we:

  • Replaced a frequently used lamp’s CFL light bulb with an LED bulb. (The CFL bulb was still good, so it will be used to replace a bulb down the line when I run out of LED bulbs.)
  • Turned the thermostat down to about 55° while we were out of the house.
  • Made sure that all lights and other electricity users aside from the refrigerator were off while we were away.

This month’s upgrade cost: $8.82

Total upgrade cost to date: $17.64

Over 28 days we used 301 KWH. Which comes out to an average of 10.75 KWH/day. Which is an expected decrease from the last billing period average of 14.2 KWH/day since we spent so much time out of the house.

We are part of the Alliant Energy Second Nature renewable energy program, at the 100% level. (In this program you can choose the amount of your energy use that you want to be matched in renewables, and we chose 100%.) So the cost of our electricity is $0.13 per KWH, for a total of $39.41.

We also used 73 Therms of natural gas heat energy. Which averages out to 2.6 Therms/day. That’s only 0.1 Therm less per day than the previous month! Even though much of the month the furnace was only heating the house to 55°, this month was much colder than the first two months of the year. Looking at this, I’m very glad that we made sure to turn down the thermostat every time we left the house, or we would have had a much higher gas bill. Also, looking at degree days this month compared to last month: 1383 vs. 1286. Our furnace was working hard this month!

The natural gas market fluctuates in Wisconsin, so there is not an easy dollar per Therm number to give you, but during this billing period we paid $60.09 for our gas use.

Our energy bill also provides these numbers for helpful comparison:

Electricity used this month last year: 714 KWH

Gas used this month last year: 73 Therms. Average temperature this month: 16° F. This month last year: 19° F. I’m going to assume that the previous owners lived in the house for the full month last year – rather than just part time like we did – and kept it at a typical 68-72°. So it’s interesting to see how just a few degree change in average temperature really makes the furnace work a lot harder to heat the house.

Degree Days this month: 1383 vs this month last year: 1342. Degree days are the number of degrees below 65° F in one day, all added together for the total 28 days of the billing period.

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Want to previous months of the Energy Efficiency Project? Here is Month 1 and Month 2

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Categories
energy house living green

The Energy Efficiency Project: Month 2

energy efficiency project month 2
Nothing like relaxing by the fire on a cold day by Counselman Collection // CC BY

January 13th – February 12th, 30 days

This month we mostly spent our time picking paint colors, getting started with the painting, figuring out where our stuff should go, and getting our compost started. As far as energy efficiency initiatives went we:

  • Replaced a dead CFL light bulb with an LED bulb
  • Turned the thermostat down from 68° F to 66° F
  • Checked the air filter on our furnace to make sure it was new/didn’t need to be replaced. It was still clean, so we didn’t replace it.

This month’s upgrade cost: $8.82

Total upgrade cost to date: $8.82

So, we didn’t expect too much of a difference in our energy usage this month. Now let’s look at the numbers!

Over 30 days we used 427 KWH. Which comes out to an average of 14.2 KWH/day. This is actually slightly higher than the 14.0 KWH/day we used during our last billing period. Womp womp.

I’m guessing this is due to putting up some post-Christmas holiday lights which are not LEDs. I know, I know, but here’s the thing. We still have these strings of working fine holiday lights, and I can’t bring myself to replace them until they no longer work. Use what you have, right? We also started some citrus tree seedlings, and had them germinating on a heating pad 24/7.

We are part of the Alliant Energy Second Nature renewable energy program, at the 100% level. (In this program you can choose the amount of your energy use that you want to be matched in renewables, and we chose 100%.) So the cost of our electricity is $0.13 per KWH, for a total of $55.90.

We also used 80 Therms of natural gas heat energy. Which averages out to 2.7 Therms/day. Definitely less than the 3.1 Therms/day we used during the previous month! Dropping the temperature on our thermostat made a difference, and really the only way it affected our lifestyle is we that we wore slippers around the house more often. Also, looking at degree days this month compared to last month: 1286 vs. 1211. Even though this months number is a bit larger than last month’s, this month’s bill was for 30 day and last month’s was for 27 days. This means that our furnace didn’t have to work quite so hard to heat our house this month, which also helped out with reducing our gas use.

The natural gas market fluctuates in Wisconsin, so there is not an easy dollar per Therm number to give you, but during this billing period we paid $65.99 for our gas use.

Our energy bill also provides these numbers for helpful comparison:

Electricity used this month last year: 744 KWH

Gas used this month last year: 97 Therms. Average temperature this month: 22° F. This month last year: 10° F. So last year was quite a bit colder than this year.

Degree Days this month: 1286 vs this month last year: 1652. Degree days are the number of degrees below 65° F in one day, all added together for the total 30 days of the billing period.

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Want to previous months of the Energy Efficiency Project? Here is Month 1.

This post contains affiliate links. Thanks for helping to support building earth!

Categories
energy house living green

Introducing The Energy Efficiency Project

Once upon a time, husby and I thought, what if we bought a house in the small town we’ll be moving to this spring. About a year ago, when I first starting envisioning this whole building earth project, I thought a good progression would be to have a house to demonstrate some of the energy efficiency, green building, and sustainable design ideas that I’ve been writing about. Not to mention we were ready to start investing in our own place inside and out.

One of the projects that I’m super excited about starting in regards to our new house is this series on The Energy Efficiency Project. Each month I’m going to explain what things we’ve done to reduce our houses energy use: upgrades, downgrades, or behavior changes. And then I’ll share the nitty-gritty with you: our monthly energy bill, and the costs, and pros and cons of the changes we’ve implemented. My goal is to be as transparent as possible in how we use energy and how we are attempting to save energy. My hope is to show how small changes can add up to significant energy savings, and maybe you’ll be inspired to adopt some of the same changes yourself.

power lines: the energy efficiency project

So first, let me share some details about our new home to give you the lay of the energy use land.

Size: 1,026 square feet. Single story, with an unfinished basement, rafter attic for insulation.
Energy using appliances: refrigerator, stove, washer, dryer, hot water heater, gas furnace, central air, garage door, coffee grinder, exhaust fan
Electronics: computer, cell phones, alarm clock, seedling starter heating pad
Light fixtures: 21 bulbs worth
Windows: approximately 100 square feet, most of which are fairly new with aluminum sills
Insulation: I’m not sure exactly, since I haven’t looked inside the walls yet, but I’m pretty sure it’s just your basic fiberglass batts. The attic has about 3-4 inches of blown insulation covering the house.
Occupants: 2 adults, one wee tender babe

The Energy Efficiency Project: Month 1

We’ve been living in the new house for about a month now. Long enough to get our first energy bill! So we have a bit of a baseline to start with.

For December 17th through January 13th this is what our energy usage looked like:

Over 27 days we used 379 KWH (kilowatt hours) of electricity. We are part of the Alliant Energy Second Nature renewable energy program, at the 100% level. (In this program you can choose the amount of your energy use that you want to be matched in renewables, and we chose 100%.) So the cost of our electricity is $0.13 per KWH, for a total of $49.62.

We also used 85 Therms of natural gas heat energy. The natural gas market fluctuates in Wisconsin, so there is not an easy dollar per Therm number to give you, but during this billing period we paid $72.90 for our gas use.

Our energy bill also provides these numbers for helpful comparison:

Electricity used this month last year: 834 KWH (!!! what did the former owners have plugged in that sucked more than twice as much electricity as we used?)

Gas used this month last year: 96 Therms. Average temperature this month: 20° F. This month last year: 14° F. So last year was a bit colder than this year which explains the higher gas usage.

Degree Days this month: 1211, vs this month last year: 1698. Degree days are the number of degrees below 65° F in one day, all added together for the total 27 days of the billing period

Now let’s see where we can go from here!

P.S. Interested in seeing a picture tour of our new house? You can check that out over on macnamania.com!

Categories
building energy living green

Happy 2015

Happy 2015Happy 2015!

How’s it feeling now that you’ve had a week to break it in?

Let’s start this year off with a bang: We bought a house!  Due to job related circumstances we will only be living in the house part time between now and June, and we will spend the rest of our time in our current apartment. This will provide us with plenty of time to get some updates and projects done before we move in for good this summer.

Now you might be wondering, what does this house have to do with this little blog? Well, it means that as we do house renovation projects, I’ll have plenty of opportunity to share with you all of those green building home renovation projects, like:

  • What are the most earth friendly paints, stains, and adhesives to use?
  • Which are the most sustainable flooring materials?
  • How do you go from lawn to organic garden (hopefully without your neighbors giving you the side-eye)?

Another blog series that I have in the works is on making a house more energy efficient. I’ll take a look at the energy usage of this house, and similar sized houses in the neighborhood, and do monthly updates on what we have done to bring that energy use down.

Aside from the house, in 2015 I’ll be continuing the series on “green” certifications in the construction and home furnishing areas. I’ll also continue to explore passive house design, integrative design, green living habits, and compost.

If there is anything you’d like to see in the upcoming year, be sure to leave a comment or drop me email.

I know I’m excited for everything that 2015 has to bring! I hope your new year is starting out shiny and bright and not too cold!

Categories
building energy

Adding Insulation for Energy Efficiency Part 1

adding insulation for energy efficiency
“Untitled” by Jesus Rodriguez // CC BY

As we continue to explore the possibility of building a house that doesn’t require a heating and cooling system, the next step is to get to know the current standard for adding insulation for energy efficiency. This is a topic that involves a bit of math. In this post, I’ll walk you through the equations that are used to determine how much insulation to add. In the next post on insulation I’ll go through two simple examples of working out how much insulation to add.

Payback Period

The typical plan for adding insulation for energy efficiency is to add to the point where you are able to cover the costs of the added material with the money that you will be saving in heating and cooling costs. The time it takes to recoup the money for energy efficiency upgrades is called the payback period. For the insulation of a residential building the average payback period that most people are interested in waiting is between 4 and 5 years. So, in order to figure out the payback period we need to consider the R-value of the insulation, and the cost of heating and cooling the house per year.

Calculating the R-Value

As you may remember from my last post on insulation, the R-Value is a numerical value given to insulation that tells you how much the insulation is going to resist the flow of heat. Determining the R-Value of an insulation material depends on a number of different factors:

  • Initial indoor temperature (Ti)
  • Outdoor temperature (To)
  • time (t)
  • surface area of the building (A)
  • The heat loss indoors (dQ)

And the equation looks like this:

R = (Ti – To) * A *t / dQ

The good news about R-Value calculations is that you usually don’t have to do them. Since the measurements to complete the calculation are done in a lab setting in a controlled environment, the insulation manufacturer provides that information for you when you choose your material.

Calculating the Payback Period

In order to calculate the payback period of adding insulation, we need to take into account the insulation and the heat system.  The payback period depends on the following features:

  • R-value of the initial insulation (Ri)
  • R-value of the final insulation (Rf)
  • Cost of insulation (Ci)
  • Efficiency of the heat system (E)
  • Cost of energy (Ce)
  • Number of days that require heat per year (t)

And the equation looks like this:

P = (Ci * Ri * Rf * E) / (Ce * (R2 – R1) * t)

You can find more information on calculating the payback period of adding insulation here.

I know looking at all these equations can be intimidating if you are interested in figuring out how much insulation to add to your house to meet the 4 – 5 year payback period. But hopefully after I work through a couple examples in my next post on insulation, it will seem manageable. Maybe you’ll even be inspired to add insulation to your own house to make it more energy efficient.

Categories
apartment living energy living green

Hang Drying Laundry in the Winter

Clothes dryers are an incredibly inefficient use of electricity. The typical dryer uses in the neighborhood of 5 kWhs of electricity, even energy efficient dryers use at best around 2 kWhs during their dry cycle. (To put that in some perspective, that’s the same amount of energy as a 100 watt incandescent bulb uses in 20 hours – or in the case of my 9 watt LED light bulbs, 220 hours!) In fact, running a clothes dryer uses more energy than any other appliance in a typical American household. That’s a lot of energy just to spin some hot air around.

These days, what with cloth diapering Cheeks McGee, I’m doing a load of laundry about every other day – 4 loads a week, we’ll say. And living in an apartment, we pay $1.50 for each cycle. Which means that if we were drying all of those loads, it would tack an additional $24 onto our expenses each month. That’s $312 a year.

So in the interest of saving energy and money, we hang dry our clothes. As I’ve written about before, in the summer heat and sun, our laundry is dry within a few hours. Now that the winter has firmly decided it’s here, we continue to hang dry our laundry, but now we hang it indoors. The shared basement laundry room in our apartment complex already had clothes lines, but in the past we’ve used a folding drying rack, the backs of chairs, the shower curtain rod, and basically anywhere else we could possibly hang a piece of clothing. It does take more than 3 hours for our laundry to be dry, but never longer than 24 hours. I bet aside from sweatshirts, most of it would be dry by morning if they hung over night. And running your clothing through the spin cycle can be really hard on it, so by hang drying we get more life out of our clothing as well.

Yes, we have to think ahead more than 2 hours if we want to wear something that is currently dirty. But right now, with the frequency we are doing laundry, that hasn’t been an issue. And in a clothing emergency, the dryer is still right there.

Categories
building energy

Insulation

A couple weeks ago I posted an Autodesk Academy video of my hero, Amory B. Lovins talking about integrative design. In this video Amory talks about insulating a house to the point that a heating and cooling system are no longer needed. I’d like to dive deeper into this idea. To start, let’s talk about some of the basics of insulation.

"Insulation Roll" by Mark Evans // CC BY
“Insulation Roll” by Mark Evans // CC BY

Why we insulate buildings

Here in the northern part of the country we typically think of insulation as necessary for keeping the heat in during the fall and winter (and sometimes spring) months. But the most basic purpose of insulation is to prevent the movement of heat. Both out of and into a structure. Insulation is also quite useful for keeping heat out of a building in the summer. So insulation can cut down on the need for both heating and cooling a building when more extreme temperatures hit. Having a well insulated home can reduce your energy use (and costs!) all year round.

R Values

Insulation materials are rated using an R Value. R value is a measure of resistance to heat flow, and is based on the temperature difference between indoors and outdoors, the area of the insulation, time, and heat loss. High R values provide better insulation than low R values. Now, walls and ceilings and floors are made up of multiple layers of different materials, and to find the total R value of the system, we add together the R value of each individual layer. Oak Ridge National Laboratory put together a recommended R value calculator based on zip code, heat source, and part of the building that is being insulated.

How buildings are typically insulated

If you rip open the drywall in one of your exterior walls chances are you will find fluffy, pink, fiberglass insulation. This is known as batting, or fiberglass batt insulation. Fiberglass batt has an R value of about 3 per inch of thickness.

Because heat rises, in colder climates it is important to have a well insulated roof or attic to keep that heat inside the building. Typically, houses have a blown insulation (loose insulation that is blown into a space to fill it), that can be 15 inches or more in thickness.

In warmer climates , where you want to keep the heat out of the house, sometimes the insulation batt has a shiny metallic side. This is put on the outer face of the wall to help reflect heat away from indoors.

Common Types of Insulation

There are many more types of insulation than the fiberglass batt or blown fiberglass.

Mineral Wool is a material that resembles matted wool, but is man made rather than sheep made. In batt form, its R value is equal to fiberglass batt, but as a blown insulation it has a larger insulation, making it slightly better for attic spaces.

Cellulose is a material made from plant fiber that can be used as a blown insulation. It also has a slightly higher R value than blown fiberglass. Cellulose can also be mixed with water, adhesive, and moisture retardant and used as a spray insulation, which has the advantage of being better able to get into nooks and crannies to seal up a space. Cellulose also has the benefit of being a vapor barrier, preventing the buildup of moisture, which can help prevent rot.

Foam board insulation can be made from polystyrene or polyurethane among other polys. The boards are made of dense foam that can be cut to fit into wall spaces, and provides a good amount of insulation for a small amount of thickness.

Foam spray insulation may be made from a variety of different man made materials such as polyurethane, and is sprayed into the walls and ceilings. Foam insulation is excellent at sealing up walls or ceilings that have small cracks and/or holes, however it is much more expensive than fiberglass insulation.

So, now we have a base understanding of insulation, next time we can talk about insulating for greater energy efficiency.

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Want to read more about insulation? Here are some good sources:
Energy.gov articles on Insulation
Insulation R Value Chart

Categories
building design energy

Amory B. Lovins on Integrative Design

I’m going to give you a little bit of homework before we get into the meat of this post. Watch this video:

(I’ve probably posted that before. I’m a wee bit obsessed with Mr. Lovins and his work)

Now let’s talk a little bit about integrative design. Integrative Design is a method of design based on working from the top down. Basically you look at the entire system – the entire car, the entire house, the entire factory, with the intention to make it as energy efficient as possible. By looking at design from the top down you ask how to make the best holistic design by intertwining the functions of the different components.

Integrative Design is different from traditional design methods which focus on optimizing each individual piece of the system and then fitting them together and adjusting how they interact. This traditional method creates the most optimized walls and plumbing and HVAC. But the integrative design approach allows you to say, what if we didn’t need the HVAC at all  (or at least not our idea of the most optimized HVAC) because we change the way we build the walls completely.

At the end of the Autodesk video Amory mentions the 10xE principles of integrative design, and I want to share those here:

  1. Define shared and aggressive goals.
  2. Collaborate across disciplines.
  3. Design non-linearly.
  4. Reward desired outcomes
  5. Define the end-use.
  6. Seek systemic causes and ultimate purposes.
  7. Optimize over time and space.
  8. Establish baseline parametric values.
  9. Establish the minimum energy or resource theoretically required, then identify and minimize constraints to achieving that minimum in practice.
  10. Start with a clean sheet.
  11. Use measured data and explicit analysis, not assumptions and rules.
  12. Start downstream.
  13. Seek radical simplicity.
  14. Tunnel through the cost barrier.
  15. Wring multiple benefits from single expenditures.
  16. Meet minimized peak demand; optimize over integrated demand
  17. Include feedback in the design.

In Amory’s lecture he talks about using integrative desing in building design for heating and cooling, in auto design for using less fuel, and in factory design for pumping fluid. Stay tuned for a bit of a deeper dive into these topics in the future, including how the integrative design principles lead to radically different approaches in each of these categories.

Categories
building energy

Tell Me More About Energy Star

Chances are you’re familiar with the blue and white logo that can be found on many types of home appliances, but do you know what being Energy Star certified actually means?

The Energy Star program was started by the Environmental Protection Agency and the Department of Energy in 1992 as a labeling program for energy efficient appliances. Energy Star is now an international standard for energy efficiency. The Energy Star label can now be applied to computers, servers, appliances, heating and cooling systems, home electronics, imaging equipment, lighting, and new homes and buildings.

In 2010 it came to light that the Energy Star label was being wrongly granted and misused. It was being granted to products that did not exist, and if a company had one product certified they were able to download the label and put it their other, non-certified products as well. Since then, a number of critical audits were completed, and the Energy Star label and certification process has been revamped to prevent these sorts of fraudulent claims.

Now each application is reviewed for approval. Products must be third-party tested in EPA approved labs. Additionally, each year off-the-shelf tests are conducted on a percentage of Energy Star labeled products to ensure that the consumer is receiving products that meet the standards.

So what does it mean if something has and Energy Star label

Each product has a set of standards that it has to meet in order to receive the label. For example, a refrigerator must save 20% of energy based on the industry minimum standard, an air conditioner must save 10%, and a light bulb must save 75% vs a standard incandescent. These standards are updated every couple years or so, in particular when at least 50% of the market is held by energy star labeled products.

The Energy Star label and buildings

There are currently Energy Star ratings for new homes, commercial spaces, and industrial plants. Buildings are evaluated for the energy efficiency of their heating and cooling systems, water management, and air quality. Buildings are evaluated by professional engineers or registered architects and have to receive a rating of 75 or higher (out of 100) in order to receive an Energy Star label.

Categories
energy living green

LED Light Bulbs

I hope you all had a lovely long weekend. Between the Holiday and adjusting to the ever changing schedule that is medical residency, Tuesday’s post got away from me. I hope you didn’t miss my wrap up on light bulbs too much. 

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LED Light BulbLED stands for Light Emitting Diode. LEDs are comprised of a semiconductor material and two leads. Basically what happens is that when the LED is connected to a circuit, a voltage is applied to the leads. This provides enough energy for electrons to jump across the band gap, and when they do, they release energy in the form of photons, or light. The color of light emitted by the LED is determined by the band gap in the semiconductor. If all this talk of semiconductors sounds vaguely familiar, it’s because it’s the same concept behind solar cells. Only in this case, the energy is coming from the wall rather than from the sun. LEDs are great as far as energy efficiency goes because they require a very small amount of electricity to produce light. They are also compact, robust, and have long lifetimes. LED light bulbs are made up of a collection of LEDs designed such that they emit a white, or slightly yellow light. Recently LED light bulbs have become increasingly available for home lighting, so let’s see how they compare to Incandescent and CFL light bulbs.

  • Light Quality: Mixed Reviews. Like CFLs I have frequently read reviews that LED light bulbs produce light that is too cold. We can probably all easily identify LED holiday lights because they have that tell-tale blue tinge to the light. I am happy to report that the LED light bulbs that I recently purchased produce a warm soft light, just like we expect are accustomed to seeing from incandescents. LED light bulbs will probably need to become more mainstream before they beat the cold blue light rap.
  • Price per bulb: Con. Standard LED light bulbs typically run $10 a bulb. If you buy them in a six-pack you can get them for more like $9, but there is definitely a bit of sticker shock that comes with spending over $50 on lightbulbs just for your home use. And if you want anything fancy, like a dim-able bulb, you’ll easily be paying double.
  • Availability: Pro. You may not be able to find LED light bulbs on the shelves of your local grocery store yet, but Target, Home Depot, and Amazon all carry them, and I imagine many other stores as well.
  • Style: Con. Similar to CFLs, LED light bulbs fit standard sockets, but the choice of bulb is limited. There are candelabra bulbs, but they don’t look the same as the incandescent equivalent.
  • Energy use: Pro. An LEDbulb that produces a comparable amount of lumens as a 60 watt filament bulb requires only 9 watts.
  • Lifetime: Pro. 25,000 hours! You read that right, a LED bulb will last more than 3 times as long as a CFL bulb. That translates into nearly 23 years of light at 3 hours a day. The LED light bulb that I recently put in our lamp will burn for longer than my youngest brother has been alive. That’s crazy town.

And bonus: LED light bulbs contain mostly recycle-able materials. Contact your local recycling provider to see if they can recycle your old bulbs. Although, you can probably wait 20 years  or so before you have to deal with that.

So the tally when comparing LEDs to CFLs and Incandescents is 3 pros, 2 cons, and 1 mixed review. Now let’s look at the long term cost.

10 year cost for burning filament bulbs in one lamp: (3 hours a day, $0.12/kwh cost of electricity, $9.00/bulb, 1 bulb) = $20.83.

And bonus: that same bulb will burn for another 13 years at that rate.

Pretty cheap when compared to the $96.84 it would cost to run the same light with a incandescent bulb, and it even beats out the $22.40 for the CFL. 

And more importantly, over that same 10 years you could save 550 kWh of electricity if you switch from an incandescent light bulb, or 55 kWh if you switch from a CFL.