“Slow Down and Save Gas” says CNN

•March 28, 2008 • 25 Comments

Here is an article on CNN that talks about how you can save gas by driving at optimum speed.

I have a similar post, but my argument was based on the gear train efficiency. This article talks about air resistance. As noted there, the resistance of air increases exponentially as the speed increases. So obviously if you are driving slower, the energy your car spends in overcoming air resistance will be significantly less. As your speed increases, this fraction increases rapidly.

This will also help explain why drafting behind a vehicle will result in fuel saving. Also this must be a factor that makes cars more fuel efficient compared to SUVs.

Reduce Food Wastage – Save Energy and Save Money

•March 24, 2008 • 18 Comments

Any talk about energy conservation usually begins with energy saving bulbs and ends with Toyota Prius. A little more educated people will tell you about blinds with reflective coating and insulating attic. It’s weird that in peoples’ mind conservation = buying stuff that conserves. Less often thought is given to how we ourselves can change, consume less, plan more and also save money in the process.

Open a refrigerator in a typical home and you will see it overflowing with stuff. Vegetables, milk, eggs, different types of fruit juices, and what not. Many of us will come home, take a look at the refrigerator, then either feel too overwhelmed with the available choices, or feel there are not enough choices, and then pick up the phone to order pizza.

On a good weekend morning, we again attack the fridge, find a lot of stuff with expiry date over, pick it and toss it in garbage.

What if we try to keep count of how much food we waste? What if we are able to cut down on this expenditure and save food as well as save money?

Here is an article that talks about the wasted food statistics in USA. A average family of four in USA tosses about $600 per year in terms of wasted food. A total about 100 billion pounds in weight, this food would be enough to feed 700 million people.

And talk about environmental costs of that food. Take a simple bread as an example.

It takes fertilizers to make crops grow. Those fertilizers are produced from crude oil derivatives. It takes oil to drive the giant machines that cut and clean the crop. It takes energy to build and operate the machines that separate the grains and chaff. Then machines are used to grind the grains, processes the flour and bakes the bread. Then again energy and more materials for packing, then transport. Here is a link to Fat Knowledge blog which further contains a link to a collection of research papers  (warning: megabyte PDF file). Conclusion: One kg bread (roughly 2 lb) takes about 4.4 MJ energy to just produce and transport to average consumer home. That comes to about 1 million calories of energy. If the bread is thrown away, then there is additional energy to transport it as trash. This means wasted money, wasted energy and wasted environmental resources.


Don’t we know that there are hungry people? Yes. Don’t we know that we are wasting money when we waste food? Yes. Don’t we know that we are wasting energy and precious environmental resources when we are wasting food? Yes we know.

Yet we continue to do so.

Because we are the byproduct of the society we live in. In today’s society, a good part of our buying decisions, like what we buy, when, how much is sometimes dictated more by business models of the companies than our individual needs.

The size of packaging, the expiry dates, the buy-one-get-one-free deals, everything kind of seduces us to do things we don’t really need to do.

I remember one thing distinctly. When I came to USA a few years back, one thing that struck me was the giant size of sliced bread loaf. Not only each bread slice was almost double of what I was used to in Bombay, the length of loaf was also almost close to double. There are smaller loafs available, but the half sized loaf almost costs the same as the big one. So you invariably end up buying the big one, because that’s more food per $.

You eat that a couple of times, and then you get bored eating that giant bread. It goes on the back shelf. You are busy and you are continuously buying more stuff. So that goes on back shelf. Some time later, you notice it, you pick it up and throw in trash.

Assuming average1$ perpound of food, $100 Billion are being wasted every year in food in USA. As mentioed above, all that money and energy to make it, transport it, store it , then discard it as trash and dump it goes waste when that food is wasted.

So what to do? How to manage food inventory better?

This inventory management question is a complex one and a lot of research has been done on this question. Here are some things we can do.

1. Start keeping track – First step of changing anything is being aware of it fully. When you buy food, keep track of it. When you eat food, make a note somewhere. When you throw away food, make a note. Do a food balance sheet somehow. This will help you identify a lot of bad habits.

2. Plan food- This is easier said than done. But worth trying. Even if you come up with a plan with one good point, it is worth in the long run.

3. The Toyota solution- Buy just in time. Do not buy a bulk of food in advance. Buying in bulk might save you some money in the food price. But your preferences change, your get bored, something else comes up. So you end up wasting food you bought and the savings go down the drain. So if possible, buy only two or three days worth of food at a time and buy that well planned. Decide how many lunches you will eat and what you will eat for each lunch, etc.

It is difficult to estimate all the energy saved when you save one pound of food from going waste. Tremendous amount of energy goes in farming, harvesting, cooking, packing, transporting, shelving, then transporting to your house, then getting picked up from your house, transporting to landfill. This entire energy spent over food life cycle will be saved.

Money wise, as mentioned above, average family spends $600 worth of food per year. Even if 15-20% of it is saved, it would mean saving about $100 per year extra (after tax saving). Nice eh? I am pretty sure you can find good use of $100 extra in your life.

Daylight Saving – Energy saving or energy wasting?

•March 4, 2008 • 20 Comments

Here is an excellent discussion on slashdot about the effect of daylight saving time on overall energy consumption.  Included is a link to Wall Street Journal article describing a study at UC Santa Barbara.

A recent legislation passed in Indiana, USA changed daylight saving time policy of the state and gave the reserchers unique opportunity to observe the effects on electricity bills before and after the change. The conclusion? “The study unambiguously concludes that Daylight Saving Time not only doesn’t save any energy, it actually wastes energy and costs more.”

Indeed at some point in time, especially around and after the world war – II, the practice of daylight saving time resulted in energy savings. People were able to use more of sunlight instead of the lights inside, and were able to save a money on electricity bills.

Then came air conditioning.

When an air conditioner or a heater runs for an extra hour because of time change, it far more than offsets the amount of energy saved by switching off the lights. As shown in one of my previous posts,  air conditioner is the biggest energy hog. The proportion of energy consumed by air conditioner is far higher and thus makes the daylight saving theory questionable.

ScanGauge II Automotive Computer- Adding Milage Tracker to your car

•January 22, 2008 • 2 Comments

For quite a while I wondered if something like this exists.

I recently drove Toyota Prius of a friend and it had this cool feature where you could tell how many miles per gallon you are getting at the moment.

There seemed to be no reason to get an external fit instrument for this purpose. But when I searched in the past, only couple of companies turned up in results and they were in Australia and New Zealand etc.

And then while browsing thinkgeek, I came across this. Nice one.

scan gauge

The best way to watch your milage is watch it often. So this should help. It shows current MPG, average MPG for the trip and a lot more data. So with this, you yourself can find out if the car gives more milage when windows are open or when A/C is running. Or if the car gives more milage when drafting behind a small vehicle or not? BYOM (Be your own Mythbusters)

If any of you have used this, I would like to know some feedback.

Do Any Companies Power Down At Night? Slashdot discussion

•January 21, 2008 • 3 Comments

Here is a nice discussion on Slashdot about powering down computers at night.

The discussion provides some excellent information, from reports of energy savings up to 33%, to reduced risk to computer network security.

Apart from the obvious benefits of saving power, there are a lot of facts people don’t understand.

1. Do computers break down if you power them up frequently? Depends on what you call frequently. If you power down every three minutes, then yeah. But if you power down every day, then it would in fact increase the life of your computer equipment, as there would be less wear and tear on all the moving components etc.

2. Is it safer security wise? Heck yeah. Every minute your computer is not online is a minute your computer is absolutely safe from lurking online dangers.

And the amount of energy it saves? Huge.. Huge savings. Today’s computers consume anywhere from 90 Watts to 300 Watts or even more depending on computer type, the jobs executed on the computer etc. This is excluding the power consumption of the monintor. Switching it off will not only save monitor power, but will also save in space conditioning energy costs.

More often than not, conservation measures like this are overlooked in corporate world. This is the problem with the system. IT admin is not paying electricity bills, so this issue rarely rises on his/ her radar.

So, if you ain’t using it, turn it down baby. It’s good for you. It’s good for mama earth.

Rechargable Batteries? How about no batteries?

•January 19, 2008 • Leave a Comment

I already have a post on my blog about rechargeable batteries and how they can save you money at the same time reducing environmental waste.

Overall, the huge difference the reusable things make cannot be stressed enough. For a product if the ratio (usable life / total life) is small, then that product not only costs more in long run, but also does more harm to the environment. In case of one-time batteries, the whole life cycle is manufacture, transport, shelving, purchase, use, trash, dispose or landfill. At each step energy is being used. Especially transport of these batteries uses large amount of energy.

So first step is to move from one time use batteries to rechargeable batteries. That would be nice, isn’t it? But here is even better solution, no batteries.

Here is a remote that has winding charger. (Google search remote control forever batteries) You wind the lever for a minute or so, and the remote is good to go for next seven days. So, you burned about 10 calories, taking you an inch closer to your weight loss resolution for the year, AND, you saved money, you saved environment.

Just imagine if all the energy , oil consumed in one time use batteries is saved. Imagine all the chemicals, lead, acid not polluting our environment. Imagine the truck full or heavy battery packages suddenly absent from the roads. And also imagine saving a few dollars in the process. Imagine your house balance sheet making a tiny move from red to black.

January Make Magazine carries a story about shake and charge remote. Since I cannot write that copyrighted material, I contacted Prof. D V Gadre, who was the brain behind that remote. He has kindly sent me a link to another of his battery-less project on youtube. It’s an electronic dice. But the charging mechanism is pretty much same as he had described in his Make magazine article.

Indeed green is the new black.

Drafting Behind A Vehicle To Improve Fuel Efficiency?

•January 8, 2008 • 7 Comments

Before a few days I watched this episode on mythbusters. They confirmed that drafting behind a big rig indeed improves car fuel efficiency, in some cases as much as by 40% (at dangerously close range).

They just tested different ranges behind the same truck. I wish they would have tested the following.

1. What happens if you are drafting behind a smaller truck? A car?

2. What happens if you are not exactly behind, if you are somewhere behind and to one side? Behind blind spot?

I am sure it is possible to take advantage of this drafting effect with some safety margin. I think everybody at one time or another has wondered about this effect or experienced it. Mythbusters just put numbers in there.

We always see migratory birds flying in the sky in a particular formation, something like a V formation. This is precisely for the same reason. The birds behind take advantage of the turbulence created by wind flapping of the bird ahead. Here is some in depth explanation of the bird formation. A group of fighter airplanes also uses such kind of formation to save some fuel on long trips. Often bicyclists and marathon runners can be seen running in formations to exploit the same advantage.

I am pretty sure the drafting effect works for quite some distance. So next time if you have a choice to drive through a lane which is empty ahead, or drive behind someone (at safe distance of course), choose the second one. You can comfortably get 5-10% efficiency boost with all safety precautions. Let us calculate what that means in terms of money. Say your vehicle original efficiency jumps from 30 MPG to 32 MPG (a modest 6.6% increase possible at very safe distance), then for every 960 miles, you will consume 30 galons instead of 32 galons. So after the cost of gas + taxes on gas , you are looking at somewhere around 6 to 7 dollars of saving. So if you drive 16000 miles a year, then it comes to around 100$ saving per year. So you are smiling. And mother earth is smiling too, because your gas consumption is around 30-40 gallon lesser, that means your CO2 emission is around 600 – 800 lbs lesser.

And 5-10% drafting advantage is at “officially safer” distance of 150 feet or more. A little less distance could be even more efficient. Even though we drive with vehicle distances less than 150 feet all the time, we should not endorse it officially, can we ? 🙂 🙂

If done safely and effectively for automobiles, this could indeed result in teamwork of cars to save fuel.

Installation of Programmable Thermostat in Few Easy Steps

•October 18, 2007 • 5 Comments

Here is it. A great webpage talking about replacing your thermostat by programmable one.

“Installing a programmable thermostat is one of the simplest things you can do to save energy and money in your home. You’ll save one percent on your heating bills for every degree it’s set back over an eight-hour period!

  • Time: 15-20
  • Cost: $25-$100
  • Difficulty: Easy
  • Tools: Screwdriver, wire cutters/strippers, pencil, level, drill, 3/16” drill bit,”

To continue reading, click here.

As I have shown in other articles on this blog, this investment will easily pay back in less than a year.  Saving money and saving the world, in one shot.

Usually it is easy to convince to homeowners, but apartment renters are hard to sell this stuff to. For that purpose, an attachment like described in this post of mine could be useful.

USB Beverage Cooler + Microcontroller = Programmable Thermostat?

•October 15, 2007 • 6 Comments

 usb beverage chiller  +  oki microcontroller   = Cheap Programmable Retrofit Thermostat

I have been thinking for a long time about this idea.

The air conditioner in my office keeps running even on nights and weekends, just because the system is old and it is difficult to fit it with a programmable thermostat. It would require several changes and would incur considerable cost.

Once I opened the thermostat in my apartment. Inside there was nothing but a thermocouple on which a glass with mercury bubble was mounted. Depending on the location of mercury bubble, the circuit would be complete or disconnected, turning the a/c on or off.

When I saw the USB beverage cooler, I thought I could  hook it up to my laptop USB port and using microsoft Devcon utility and writing a batch file or something, I can turn this device on and off at a specified time. The cooling produced by this device can be used to fool the existing thermostat to turn the air conditioner off.

But glitch 1. This device is not registered as a device at all in the USB devices list. It powers up when connected to USB and starts cooling, but does not show up in USB devices list.

Then I connected it to a USB hub. Then it did not start at all. On reading the documentation, I got that this will not work with USB  hub because this device eats the max power provided by USB port and thus hub cannot support it.

This is the last option I have. I have already posted it on halfbakery and got some good feedback.

Don’t have time to make this hack happen right now, as some other things are keeping me busy. But as soon as I get some time, I will give it a shot.

As suggested in halfbakery discussion, this could be a big help for rental apartments.

Any comments?

Slashdot Story On Solar Power

•August 28, 2007 • 4 Comments

Slashdot is carrying a post on solar power growth, 45% per year according to the article. Discussion and comments are interesting as always.

The biggest advantage of solar power- the power availability curve closely follows power usage curve. Meaning the maximum power is available mid-day when maximum power is being used.

A big reason why we need coal fired power plants is that they can start cranking power at the flick of the switch, when we want most. But Solar power gives that to us naturally.

No moving parts, no emissions, light to energy year after year, 25-30 years.  So why it has not caught up so far?

One big reason I think is the spread of information technology and electronic equipments. That industry is competing with solar industry for silicon, thus driving silicon prices high. At some point in future this conflict can turn into synergy (say somebody figures out how to extract silicon from electronic waste), and then Solar Energy will enter Moore’s law curve.