Tag Archives: efficiency

Home Solar Power: Getting Started

home solar powerA couple weekends ago I had to opportunity to attend a class entitled “Do It Yourself Photovoltaics” which was put on through our local garden center. The man who taught the class, Mr. Jon Passi, stressed that his goal was to make solar power projects as accessible as possible to others, and encouraged us to share what we learned from his class with our neighbors, so I’d like to share a bit about what I learned with you.

home solar panels 3

How Much Solar Power Do You Need

The first step to getting a home solar project going is to figure out how much power you need. Most power companies these days will provide graphs of your power use for the past year, so you can see how much electricity you use each month. When you look at this graph you’ll probably see that you have a season of the year where you use quite a bit of electricity, and a season where you use less. For my family, we use more electricity in the winter time than the summer, because we are more likely to be inside, and because it is dark during more of our waking hours. But if you might find that the opposite is true for you, depending on your habits and your home.

So, take a look at your energy use over the course of a year. With solar power, you produce the amount of electricity you use each day, and then start over again the next day. Figure out what your average monthly electricity use is. Then divide that number by 30 to get an estimate of your average daily electricity use. For the average American family, this number is somewhere in the range of 20 – 40 Kwh per day.

Your average daily electricity use is what you’re shooting to produce with a home solar power project. Yes, some days you will use more, but if you’re still connected to the power grid, you’ll be able to draw whatever extra you need from your power company. And on other days you will use less electricity than the average, and on those days you will be able to sell back any extra that you produce to the power company. It will all even out in the end, and usually in your favor – depending on your power company, you’ll be able to sell your extra electricity to the power company for more than you are paying for the little bit you need from them on cloudy days or days when your energy use is a bit higher than average.

home solar panels 2

How Much Will Home Solar Power Cost

The next step is to figure out if you can lower this number. Home solar projects are still pretty expensive, so the more you can lower your daily needs, the less you need to invest in supplying that power. Before you start shelling out dollars for solar panels, maybe it’s the right time to upgrade to a more energy efficient refrigerator, dish washer, or washer and drier. Maybe it’s time to commit to hang drying your clothes. Make sure your computer, television, and gaming systems are all on power strips that you turn off when you’re not using them to reduce the amount of phantom load your electronics are drawing. Upgrade your lightbulbs to LEDs. Before you spend $10k+ on solar panels, spend a couple months committing to lowering your energy use, and then recalculate your average daily electricity use.

A good rule of thumb right now for how much a home solar power project is going to cost you is to multiply your average daily electricity use by 1000. So if your home uses 22 Kwh of electricity per day, the cost of a project big enough to cover your entire energy needs would be about $22,000.

Before you get bug eyed at the cost of a home photovoltaic project, keep in mind that there are currently lots of opportunities for energy rebates. The federal government will give you 30% of the cost of the project in rolling tax breaks. (Rolling means that if you don’t use the whole 30% the first year, you can take the remainder the following years until you reach the full 30%.) Many power companies are also offering rebates for home solar projects right now as well. Mr. Passi gave us some examples of projects that he worked on in the past couple years, and many times the after rebate costs were around 60% of the total cost of the project.

Also, keep in mind that solar panels take up quite a bit of space. You likely won’t have enough room on your roof (especially in a city or suburb situation) to even install enough solar to cover the entirety of your daily use. When you look at how much solar power you can actually install on your house, the scope of your home solar power project may drop significantly. And even if you’re only supplying some of your home electricity needs, on sunny summer days, you will likely still produce quite a bit of extra electricity to sell back to the grid.

I have plenty more to share on this topic, but I think this is a good start for today. In the future I’ll get into more about the components you need for a home solar power project, and use our house as an example for figuring out how much electricity you need to produce and the costs of completing that project.

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Adding Insulation for Energy Efficiency part 2

The last time we checked in on the topic of insulation and insulating a house to the point where it wouldn’t need a furnace was back in December. Sheesh. The cold has broke here in the northern great lakes region, and while there is still a chill in the air some days, we seem to be headed right into spring. The good news is, insulation is not just a winter topic. Good insulation in your home will help keep it comfortable all year long. And keep your energy bills down. And so we forge ahead with adding insulation for energy efficiency.

Previously, I walked through the calculations to determine the payback period for adding insulation. Today let’s look at a couple of examples of how that might work our in practice.

  • 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 Heat Degree Days for the year (HDD)

And the equation looks like this:

P = (Ci * Ri * Rf * E) / (Ce * (Rf – Ri) * HDD * 24)

OK, take a deep breath. We’re about to do some math!

Example 1: Fiberglass Insulation Upgrade

For our first example, we’ll use the following situation: A house in Wisconsin is going to have its insulation upgrades. It currently has fiberglass batting with an R-value of 13, and will be upgraded to fiberglass batting with an R-value of 19. The cost of the new insulation is $0.41 per square foot. The house is heated by a natural gas furnace that is 85% efficient. The cost of natural gas in Wisconsin is $0.82 per therm, and 1 therm is equal to 100,000 Btu (British thermal units). The number of heating degree days for Wisconsin is 7499. We want to find the payback period for the new insulation.

So, breaking down our equation, we have:

Ci = $0.41 per square foot

Ri = 13

Rf = 19

E = 85% = 0.85

Ce = $0.82 per therm = $0.0000082 per Btu

HDD = 7499

P = (0.41 * 13 * 19 * 0.85) / ((0.0000082) * (19 – 13) * 7499 * 24)

P = 9.7 years

Wowza! That’s more time than I was expecting. So what are the key factors here that could cause this to payback period to go down? Well, first of all, with a little more looking, you might be able to find a better price on your insulation than a quick tour through the Home Depot website gave me. Also, natural gas in Wisconsin is pretty dang cheap right now, all things considered. But as more cities and states do things like ban fracking for natural gas, that cost could go up significantly, which would obviously bring the payback period down.

Example 2: Sprayed Foam Insulation – How much can we get?

What if instead of replacing all that R-13 fiberglass insulation with R-19 fiberglass insulation, we wanted to replace it with spray foam insulation?

Spray foam insulation has an R-value per inch of foam thickness. You can increase the total R-value by spraying a thicker layer of foam. There are tons of options available as far as spray foam goes, but for the sake of this example, we will use this Dow Froth Pack as our insulation. This spray foam provides R-6 per inch of thickness, so 1 inch has R-6, 2 inches has R-12, 3 inches has R-18, so on and so forth.

In this example, instead of calculating the payback period for the spray foam insulation, we’re going to see how thick of an insulation layer we can “afford” to apply, given the same payback period as the upgrade from R-13 to R-19 fiberglass. In other words, we are going to solve for Rf.

So, breaking down our equation, we have:

Ci = $1.01 per square foot

Ri = 13

Rf = x

E = 85% = 0.85

Ce = $0.82 per therm = $0.0000082 per Btu

HDD = 7499

P = 9.7 years

Through the magic of algebra, we can rearrange our equation to solve for Rf:

Rf = (P * Ri) – P – ((Ci * Ri * E)/(Ce * HDD * 24))

Which looks gross, but it’s really just a matter of plug and chug at this point:

Rf = (9.7 * 13) – 9.7 – ((1.01 * 13 * 0.85)/(0.82 * 7499 * 24))

Rf = 10.67, or about 1.75 inches thickness of the spray foam insulation.

So, for the same payback period as with the fiberglass insulation, we’d actually be downgrading from R-13 to R-10.67 with the spray foam. If we wanted to increase to the equivalent R-value, our payback period with the spray foam would be nearly twice as long!

But then what’s all the fuss about spray foam insulation? Why would anyone use it if the return on investment is apparently so low? Well, the R-value of the insulation isn’t telling you the whole story here. Remember the walls of your house are not just made out of batts of insulation. There is also the framing, the siding, the sheet rock, and all the other layers to consider. And those layers typically have small cracks and crevices where the heat can leak quite easily. One of the benefits of the spray foam insulation is that it fills in and seals all those leaky spots. So not only do you have the impact of the insulation layer, but you’ve increased the insulation abilities of all those other layers as well. Insulation can be one of those things were whole is greater than the sum of the parts.

Onward, Energy Efficiency Warriors. Next time we visit this topic we’ll get to the big finale: Can you insulate a house enough such that you don’t need a furnace???

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The Energy Efficiency Project: Month 2

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.

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

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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!

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!

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.

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.

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.

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.

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. 

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.