Monday, December 13, 2010

Carbon Footprint: Transportation

Transportation is the biggest emitter of CO2 in most American families. Here is our transportation carbon footprint estimation.

We have two fairly efficient vehicles: a 1997 Ford Escort, and a 1998 Honda Civic. We also have a 2001 Suzuki GS500 motorcycle as a spare vehicle.

To estimate our usage, I looked at when we bought each vehicle, and how much miles we have put on them.
Ford Escort purchased in 2004 at 120,000 miles. It has now 235,000 miles, so that is about 20k miles per year.
Honda Civic was purchased in early 2008 at 145,000 miles. It has now 193,000 miles, so about 20,000 miles per year.
Because we moved closer to work, I reduced out estimated yearly mileage to 15,000 miles per vehicle per year. The estimation is conservative, my commute was reduced from 28 miles to 18 miles, 35% reduction, but I applied a 25% reduction for both vehicles.

We can now estimate how many gallons each vehicle uses per year:
Ford Escort gets 33MPG, or 454 gallons per year (15k miles).
Honda Civic gets 37MPG, or 405 gallons per year (15k miles).
Note that the MPGs are average, measured by myself, not advertised mileages.

Our total gasoline use is 860 gallons per year.
At 8.8Kg of CO2 per gallon, that is 7.5 tons of CO2 per year.
The average American family emits 12 tons of CO2 for transportation (and another 12 tons for household operations), so we are about 38% lower than the average.

Since this blog is about Carbon reduction, lets see how much we can reduce that, and for how much money.

The Ford Escort as a newer engine in it (100,000 miles), so we can keep this vehicle for when we want to haul cargo or people.
For my commute, I can use my motorcycle, and I can replace my Civic by a hybrid for bad weather. My wife may use the hybrid when I use the motorcycle.

Here is an estimation of each vehicle mileage for a year:

Suzuki motorcycle = 10,000 miles at 70MPG = 143 gallons per year.
Honda Insight = 15,000 miles at 70MPG = 214 gallons per year
Ford Escort = 5,000 miles at 33MPG = 151 gallons per year.
Total = 500 gallons per year, or 4.4 tons of CO2, a reduction of 3 tons.

How much that reduction would cost us?
A used Insight costs about $7k.
Payback would vary with gasoline price:
At $3/gallon, 6.5 years
At $4/gallon, 4 years 10 months
At $5/gallon, 3 years 11 months ~ 4 years.

One important point is that the Honda Civic will need replacement soon, so considering the full price of the Insight is not a fair calculation. Instead, I should compare how much I would pay for a non-hybrid vehicle, about $3500 for something like a Cavalier, so the true cost of the hybrid system would be $3500 for my case. This would put the payback time at:
3 years 3 months at $3/gallon
2 years 5 months at $4/gallon
2 years at $5/gallon.

From this data, I can decide how important changing vehicle would be on the priority list. Initial capital investment and payback time are the prime drivers, since future savings will pay for coming projects.

Thursday, December 9, 2010

Carbon Master Class of 2010 !

The WSU Extension Carbon Masters Class of Fall 2010 ended yesterday. The training included the development of an outreach project. As an engineer, I am not good at outreach, so my approach is to lead by example, to modify my home with a minimum upfront expense, and maximum use of DIY projects. Call it "Climate change activism, an engineer's approach", or something like that. The focus of the projects would be to save money by saving energy, because saving appeals to everyone, even climate skeptics. The project presentation appears very technical, but by detailing every step of my projects, I hope to make visitors say "I want to do that!" and help them do so.
I will be using a lot of resources from by Gary Reysa, I highly recommend that you browse his fantastic website. This is an encyclopedia of solar DIY how-to. One of my earlier projects is actually linked to his greywater section.
To avoid lengthy reading, and also because I still have a lot of planning, calculation, research and design to do, I will post the whole project by chapters, one chapter every few days as I figure out the details.
Today I will lay out the different projects included in my outreach plan, so here we start:

Chapter 1: Assessement of our home energy use.
We moved in in February 2010, and we have now enough data to assess our energy usage. First step will be to get that data from PUD and log it into this website. I hope to also do some analysis as to where we can make changes with quickest payback. Consequently, the following chapters content and their order may change.

Chapter 2: Greywater system.
This system was already running in my previous home, and is described in this site (and linked to from at:
[ My Greywater System ].
Our new home presents some challenges regarding the implementation of the surge tank (below ground), the reedbeds will need to be frost protected (the previous reedbed died during the 2008 blizzard). Re-installation will require some re-design as well.

Chapter 3: Rainwater System.
This too was running in our previous home, the rainwater was used to flush the toilet. The system included a first flush diverter that worked very well until the 2008 blizzard cracked it (frost damage). Some lesson learned and consequent redesign required! Installation more challenging due to house setup, but a lot more roof area, increasing potential.

Chapter 3: Test of a Radiant Hydronic Wall.
I will remodel a room in our basement, that is unused at the moment. This is the coldest room of our home, and is a prime candidate to test a more efficient heating system. I will try a radiant wall, as described in The heating fluid will be electrically heated initially, to prove the concept of the radiant wall.

Chapter 4: $1K solar hot water system.
Following multiple examples, I will build a solar collector and storage tank to heat water. The collector will initially heat the room modified in chapter 3, then the size of the collector will be increase as more exterior walls are converted to radiant, in order to keep the system as balanced as can be while it is been installed.

Chapter 5: Solar Hot Water
The electric hot water heater will be downsized, and a solar hot water tank will be installed upstream, so that the hot water is pre-heated by the solar system. The hot water tank will use the excess heat from the hydronic system. A hot tub will be connected to the hydronic system as well, in order to dissipate the extra heat and avoid damage from excessive water temperatures.

Chapter 6: Super-insulation.
All exterior walls of the house will be thickened. The radiant walls modified in the previous chapter already received extra insulation. This chapter will be about adding that same extra insulation to the remaining non-radiant exterior walls, so that the whole house shell has been upgraded. Attic insulation may also receive extra insulation if needed. Not much can be done to the slab though.

Chapter 7. Controlled ventilation.
Closely following insulation improvements, controlled ventilation will provide fresh air, avoid back-draft from the wood stoves, and reclaim the heat from the exhaust stalled air.

Chapter 8: Drain water heat recovery.
I will design a system replicating the GFX, to reclaim heat of the waste water from showers and other warm water users. This chapter will require careful design and assessement, as I am not sure the amount of energy reclaimed is worth the material to reclaim it.

Chapter 9: It never ends.
There is always improvements possible. Here are a few...
After at least one year of rainwater usage, it will be a good time to analyze the water, and determine if it is suitable for higher "grade" of use, such as laundry. The greywater system will also be assessed after one year of use. If the reedbeds filter the water sufficiently so that it can be stored for 24 hours or so, then the greywater may be used for toilet flushing, freeing more rainwater for laundry, or showers, or any suitable use. Our rainwater would be used 2 times before ending in the sceptic system.
The wood stoves may be connected to the hydronic system, to distribute their heat though the house. Not an easy task.
A photovoltaic system may be installed using laminates, that I would assemble to make solar panels. On top of the low cost of laminates (~$1 to $1.5 per watt), they may qualify for maximum payback from PUD (manufactured in WA?).

Chapter 10. Getting them to come.
As our micro-farm develops, we hope to have more traffic to our home. The glaring solar collector and blooming reedbeds should raise curiosity. That is when the real outreach will start.

What about codes and regulations? Each project will be done following as closely as possible existing regulations, If regulations don't exist yet, then best practices will apply. It is possible some of these projects will be scrapped due to impossibility to meet codes. I welcome all advises on this important matter.

Disclaimer: Don't try that at home!

To be continued...