If you have wanted to try your hand (or pointer, electronic pen, etc) at more advanced image editing than just cropping and basic color enhancement, you should really try out The GIMP. It is available at http://www.gimp.org/. The software is freeware with no fees for use. It is just like the high end Photoshop software, but the cost is much more reasonable.
The software does have quite the learning curve, but it is similar to other advanced image manipulation programs. Once you learn the basics of working with layers and start experimenting with the different image effects, you will get the hang of it. There are tutorials online you can use that will teach you how to do specific things, but at the same time teach you shortcuts, methods, and easy navigation through the program. There are also books you can purchase to speed the process.
Monday, January 28, 2008
Thursday, January 24, 2008
Graphics
Now that I'm back to the blog, I hope to make it look a little sharper. I was playing around tonight learning some graphics tools and created the "Jeff's Blog" image shown here.
This is my first creation like that, and I'm surprised at the amount of work it takes. There are five layers of different colors, textures, and text to create what you see, including a shifted layer to make a shadow. I think it looks good. I will hopefully make another more detailed version soon to place at the top. Then I will update the photo on the side, or just include it in the main header.
This is my first creation like that, and I'm surprised at the amount of work it takes. There are five layers of different colors, textures, and text to create what you see, including a shifted layer to make a shadow. I think it looks good. I will hopefully make another more detailed version soon to place at the top. Then I will update the photo on the side, or just include it in the main header.
Wednesday, January 23, 2008
A number check on ethanol
I haven't posted on here for a while. I've been very busy over the past six weeks.
The grad school work has kept me busy. Recently I have been looking at biomass, which led me to do some interesting calculations.
Here is the question (when you get into engineering, all questions have multiple parts): If you have an acre of corn grown and converted to ethanol, how much energy do you get? How does it compare to the solar energy striking the ground? How does it compare to a single wind turbine?
From various sources, the amount of ethanol per acre comes out to about 450 gallons. The energy content is equivalent to about 40 GJ (gigajoules, it didn't take long for me to run away form the inferior US units). To put 40 GJ in perspective, that is equivalent to about 11,000 kilowatt hours. That is a deceiving number, because the energy is not available except as heat in that quantity. If the ethanol is used to drive an engine to power a car or produce electricity, the actual amount of energy available will be about 3,500 kWh.
Solar energy strikes the land at a year round average in Iowa of about 160 Watts per square meter. Working out the numbers, 5,650,000 kWh of solar energy strikes an acre annually. Once again, not all can be harvested. Lets figure a photovoltaic panel is used with 10% conversion efficiency, and they are placed to collect about half of the energy available. Even with these low numbers for efficiency, 282,500 kWh of electrical energy is produced. This is about 80 times the amount of energy gained from ethanol.
Wind energy varies, but typical wind turbines output between 4,500,000 and 6,000,000 kWh a year. Each one takes up 1/4 acre of land. They must be spaced apart or else the turbines will interfere with each other and disrupt the wind. Working out the numbers, it takes about 37 acres for a wind turbine. From a one acre plot of land, a wind turbine will output about 120,000 kWh of energy, or about 34 times the output of growing corn for ethanol.
To put the numbers in perspective, if fields were not cultivated at all and turned into a natural prairie with wind turbines covering the landscape, about the same amount of energy would be produced. If we covered 600 square feet of a house roof in solar panels, we would output the equivalent energy of an acre of corn (43,560 square feet).
None of this analysis takes into account the energy input for ethanol. A wind turbine must be constructed, and it typically pays back the amount of energy for construction in a few years. Photovoltaics are the same way, with payback of a few years. Very little fuel consumption goes into the annual upkeep of the wind and solar technologies, compared to the huge amount of fuel that goes into an acre of corn for ethanol.
The problem with any biocrop is the efficiency of photosynthesis. The efficiency is less than 0.5% at best. Corn is only growing for a few months out of the year, and the rest of the year the field is bare and not collecting energy, further reducing the amount of solar energy collected.
Does it require more fuel to make ethanol than we get from the fuel? I am not totally sure. A lot of the pro-ethanol studies are done by pro-ethanol groups. I did a calculation the other day showing that it takes about 1,000 kWh of energy to make the ammonia to feed an acre of corn. Considering we only get 3,500 kWh out of the crop, and I didn't account for transportation of ammonia, corn, ethanol, or the huge amount of natural gas used at the ethanol plant, the net energy gain is going to be very very small.
Keep in mind that the energy food energy consumption of a human is about 2.5 kWh per day. We can feed thousands of meals off of that acre of land if used for food. We can fuel an SUV for less than half a year on the corn energy from an acre of land. Which one should be our priority? Which method of land use (solar, wind, corn ethanol) is the most efficient and best use of our resources?
The grad school work has kept me busy. Recently I have been looking at biomass, which led me to do some interesting calculations.
Here is the question (when you get into engineering, all questions have multiple parts): If you have an acre of corn grown and converted to ethanol, how much energy do you get? How does it compare to the solar energy striking the ground? How does it compare to a single wind turbine?
From various sources, the amount of ethanol per acre comes out to about 450 gallons. The energy content is equivalent to about 40 GJ (gigajoules, it didn't take long for me to run away form the inferior US units). To put 40 GJ in perspective, that is equivalent to about 11,000 kilowatt hours. That is a deceiving number, because the energy is not available except as heat in that quantity. If the ethanol is used to drive an engine to power a car or produce electricity, the actual amount of energy available will be about 3,500 kWh.
Solar energy strikes the land at a year round average in Iowa of about 160 Watts per square meter. Working out the numbers, 5,650,000 kWh of solar energy strikes an acre annually. Once again, not all can be harvested. Lets figure a photovoltaic panel is used with 10% conversion efficiency, and they are placed to collect about half of the energy available. Even with these low numbers for efficiency, 282,500 kWh of electrical energy is produced. This is about 80 times the amount of energy gained from ethanol.
Wind energy varies, but typical wind turbines output between 4,500,000 and 6,000,000 kWh a year. Each one takes up 1/4 acre of land. They must be spaced apart or else the turbines will interfere with each other and disrupt the wind. Working out the numbers, it takes about 37 acres for a wind turbine. From a one acre plot of land, a wind turbine will output about 120,000 kWh of energy, or about 34 times the output of growing corn for ethanol.
To put the numbers in perspective, if fields were not cultivated at all and turned into a natural prairie with wind turbines covering the landscape, about the same amount of energy would be produced. If we covered 600 square feet of a house roof in solar panels, we would output the equivalent energy of an acre of corn (43,560 square feet).
None of this analysis takes into account the energy input for ethanol. A wind turbine must be constructed, and it typically pays back the amount of energy for construction in a few years. Photovoltaics are the same way, with payback of a few years. Very little fuel consumption goes into the annual upkeep of the wind and solar technologies, compared to the huge amount of fuel that goes into an acre of corn for ethanol.
The problem with any biocrop is the efficiency of photosynthesis. The efficiency is less than 0.5% at best. Corn is only growing for a few months out of the year, and the rest of the year the field is bare and not collecting energy, further reducing the amount of solar energy collected.
Does it require more fuel to make ethanol than we get from the fuel? I am not totally sure. A lot of the pro-ethanol studies are done by pro-ethanol groups. I did a calculation the other day showing that it takes about 1,000 kWh of energy to make the ammonia to feed an acre of corn. Considering we only get 3,500 kWh out of the crop, and I didn't account for transportation of ammonia, corn, ethanol, or the huge amount of natural gas used at the ethanol plant, the net energy gain is going to be very very small.
Keep in mind that the energy food energy consumption of a human is about 2.5 kWh per day. We can feed thousands of meals off of that acre of land if used for food. We can fuel an SUV for less than half a year on the corn energy from an acre of land. Which one should be our priority? Which method of land use (solar, wind, corn ethanol) is the most efficient and best use of our resources?
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