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I was thinking about this the other day. Would it have been better to fly or drive to Florida. This would be strictly from a CO2 emission aspect only.

What would my CO2 emission have been from flying. I found a great site for figure this out. Plug in my information and I get 319 lbs of CO2 per person. My family is only 4 people. So that is equal to 1276 lbs of CO2 for the round trip. (I did not use RFI, the definition of RFI is; radiative forcing is the difference between the radiation energy coming into the earth (primarily from the sun) and the radiation energy leaving the earth. To me it muddies the water and I did not use it.)

What would my CO2 emission have been from driving. I am going to assume a 25 mpg car. Now, the car emits the same amount of CO2 if there is one person or eight. (maybe a little more for weight but still) So a 25 mpg car emits 0.78 lbs of CO2 per mile. Google maps states it is 990 miles to Orlando. That would be equal 772 lbs of CO2 produced.

Looks like the car win easily. Even if you drove a gas guzzling SUV you would still be ahead of the plane. I don’t think I will fly for any destination that is under a six hour car ride. Airports are still just a hassle. So now I can feel even better about my car driving preference. (We took the plane down to Disney. A 15 hour car ride with a 2 and 5 year old just did not sound like a very good time.)

 

For more information on Carbon Credits check out solarhome.org’s Carbon Credit E-Book.

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I think I purchased too much. By the looks of it I have about R-60 up there now. I would show a picture but it just insulation. All in all, it took about 3 hours. That included adding the deck boards to walk on. I really believe that I only had maybe R-30 before. It just did not look very deep. I understand that blown in insulation settles but it looked less than 12″ thick. With this additional fluff, I hope to reduce my gas usage this winter by 10%. The total cost on the insulation was $175. A 10% reduction in gas usage would be about $100. This will payback in less than two years. Since this will also help reduce the temperature difference between the upstairs and downstairs of my two story house I think that alone has made it worth it.

So I am visiting Florida. It is hot and Humid. My first question, do people even have heaters in there homes? I am sure they have electric resistive heaters. I would think they get used very seldom. The next question I had, why doesn’t everyone have a solar hot water heater. Just running the water thru the collector without any sun would at least get it up to ambient temperature. Which right now is 91 degrees. The next question is, why doesn’t everyone have solar modules on their roof? With the great solar insolation that Florida receives it would seem to be an easy option. It is easier to cool down from 90, then it is to heat from 20. Since it seems to rain almost every day, a rain barrel would have you covered on the days that you get missed by mother nature.

Maybe my old solar books just have a nostalgic sense about them. But, I think the solar books / alternative concepts genera don’t have the same feel about them. Either they are too technical or they state, “leave it to the pros.” The books I like are out of print. Why? Anybodies guess? Maybe the DIYer is a dieing breed.

The New Solar Electric Home, I have the first edition. Now there is a new 3rd. edition. But I will spend my $40 on something else.

Achieving Energy Independence – One Step at a Time, nice pictures, easy to read, explain the math.

Wind Energy Basics: A Guide to Small and Micro Wind Systems, link is for new edition, I did not know that!, just came out this year, this is a good basic wind book.

Solar Electric Independent Home Book, Just a great all around book on solar, very easy to understand.

Solar Homes and Sun Heating, this is from 1976, still relevent even today. I think I got it for $4.  

In my quest for continually reducing my utility usage, I am going to try some cheap dryer balls. The name I keep seeing on the Internet is Nellie’s Dryer Balls.

I did find a good review on dryer balls with some real world data. And the folks on amazon have good things to say about them. (Not about energy savings.)

Okay, so while I was reading some reviews on amazon.com I found this website.

If is for Wool Dryer Balls. They only cost a few dollars more and are not made of plastic. Call me a sucker but I just bought them. I will let you know how they work when I get them and try them out.

When it comes do to it, not much at all. Since I replaced my gas water heater, my gas usage has been about zero. Last month I used 2 CCF. This month I used 1 CCF. If I had an electric dryer that would have been an extra 58kW and 29kW respectively. So to have to pay almost $15 a month for gas, when all I would have payed extra for electricity was $0.60 seems  a bit ridiculous.

I am going to wait to replace my furnace/AC with a Heat Pump until next year. The outlook looks good for Natural Gas prices. If I can get one more year at of my old equipment with little chance a new heat pump would save me much money, the better. It would be nice to have a gas bill below $150 this year.

One of the biggest variables in the power output of your solar array, besides positioning, is temperature. Let us look at the SMA America Sizing Tool. The input variables would be SB 5000US,  Evergreen Solar ES-B-195-fa2, and Irradiance of 1000W/m2. I will use my Zip Code 46142. You can use your location if you like. Temperature, -22 F and 104 F. Then click “Get Sizes”, then “Predicted Output”.

If you look at the 20 panels data points for the inverter output. -22F is equal to 4090 Watts 104F is equal to 2812 Watts. The difference is 1278 Watts!!!

Now lets look at something more typical. 23F is equal to 3633 Watts 86F is equal to 2994 Watts. The difference is 637 Watts!!! With a temperature difference of 63F. The wattage difference is over 15% of the total array wattage. The specification that you want to pay attention to is called, Module Temperature Coefficient of Power (PKpmp), in this example, -0.49%. As the temperature goes down, the power goes up. Standard Test Condition for temperature is 77F.

The benefit of the increased array output at cold temperatures is that they occur in Winter. With Winter, comes a decrease in solar insolation. A a really cold day you could potentially have a higher peak output then you would in the summer.

A good thing to note, Kaneka make a panel that only has a Coefficient of Power -0.20%. At the aforementioned temperature extremes, the wattage difference is only 609 Watts as compared to the 1278 Watts. Over time, that can make a big difference.

What is the “edge-of-cloud effect” and how can it cause a solar array issues?

What is it? Well, just as the cloud begins to cover the sun or when the sun is emerging from behind a cloud, there is a sudden burst of energy that produces more power than normal. This is caused by light refraction. Refraction can concentrate the sunlight while the edge of the shadow passes by. The result is a boost in module voltage output. On a day with bright blue skies and fair weather cumulus clouds, the effect is quite noticeable.

So how can you account for this increase in output. Common practice is to add 20% to 25% to the amperage rating of the solar controller. But many controllers today are the MPPT type. They track the arrays Maximum Power Point on its IV curve. As the edge of clouds start causing over-irradiatance. The MPP voltage starts to rise, so too, does the current. The MPPT controller then adjusts the voltage up to correct for this effect.

Take for example a Sunny Boy 5000 Watt grid-tie inverter. The lower the voltage of the array the better the efficiency. Of course the design of an array depends on the solar panels but you should never design around the highest voltage under standard conditions. In this case 480 VDC. Me, I would design around 350VDC to 400VDC under normal operating conditions. This would allow for the MPP to move around where it wants to.

Basically, solar controller can handle brief overages of current, but not voltage. The edge-of-cloud effect is only going to be a problem when it is very cold outside and passing clouds. You can use this sizing tool for SMA Sunny Boy Products. Also, solar panels have a Voc (open circuit) and a Vmp (max power). for a 12VDC panel Vmp may actually be 17VDC and Voc around 21VDC. Since the edge-of-cloud effect normally occurs when the inverter or controller is running you already have some extra wiggle room.

(I guess you could have a rolling black during the day and have your grid-tie inverter shut-off. But then you would also have to have record cold temperatures. But then it would be winter and you would have less transmitted light because it has to travel though more atmosphere at an oblique angle. Plus you would have to have perfectly clean panels. As you can see, not likely to happen any time soon.)

My wife and I have used a butter keeper for almost a year now. The only time I use a non-butter produce is on my corn-on-the-cob. (Sweet corn with sweet butter is too much for me.) This butter keeper keeps the butter from go rancid while at room temperature.

The butter will stay good for about 30 days. This is because of the design of the keeper. You put about four ounces of water into the cup and then take the cup of butter and place it upside down in the cup of water. This makes a seal keeping the butter fresh at room temperature. I have only one complaint. It is not big enough. It hold one stick of butter. I fill it about once a week.

I don’t think I will ever switch back to a Margarine type product. Just for some background information about Margarine.