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theWatt Podcast 73

Panel discussion podcast with Jeff, Leslie, Flora and Ben. Topics include Flora's geothermal installation, green jobs, food prices, solar power tax credits and electric cars.

Topics/Show Notes:
Email from Stephen about Geothermal:

Re: theWatt Podcast 73

Really had a good time with this discussion, Ben...

Re: theWatt Podcast 73

Yeah, I think the only thing that could have made it better is if we were actually drinking beer.

Einstein quote

So, after double checking my facts...I may be wrong about Einstein saying that once the bees start dying we have 4 years. I guess that's what you get for listening to a friends who knows a guy.

Re: theWatt Podcast 73

Hi Ben,

Great show, a few thoughts:

>The cheapest car in the world is electric, its marginally cheaper that the TaTa. Getting energy usage per km down allows batteries to be feasible now!

>Green jobs overcomes the fact that climate change is not a voting issue; it has to be framed as an economic issue. A second political priority may be healthcare and in the UK we are currently linking this with the fight against obesity, cycling and air qaulity.

>Best quote 'huge typewriter lobby'.

>The tata does better than the golf deisil or the prius you taked about, i think it's 70-80mpg.

>Mobility is the problem, cars are part of the solution but are an awful answer for urban areas. Mass transit including Bus Raid transit and Light and Heavy rail are making a comeback. fixed

I put up a bad link to the mp3's fixed now.

Re: theWatt Podcast 73

Great fun, thanks Ben!

Re: theWatt Podcast 73, concepts behind geothermal heat pump

well done with podcast 73.

An air conditioner is a heat pump. When heating your house, a heat pump can be run backwards to change the orientation of the thermal cycle and thus provide heat to your house in the winter.

Heat pumps are not practical here in Cleveland Ohio where I live because the extreme winter temperature differential between the outside air and the required output temperature of the air discharge in the house. They use them in California just fine.

One way to make the heat pump practical here is to lower the temperature differential between the desired output and the discharge side. This is where geo thermal heat pump comes in. The earth is at a constant temperature.

Consider the more familiar the air condition cycle. Waste heat is discharged during the summer. It would take less energy to run the air conditioner if the thermostat was increased by a few degrees. There is a less obvious chose to save energy. Assume that there is a constant heat gain through the homes insulation (and however heat gets into the house). By exchanging energy not with the ambient outside air but through a cooler geothermal heat exchanger, a larger temperature differential will require less energy.

The geothermal heat pump is about saving energy via decreasing the amount of energy required to compress gas by way of exploiting the constant temperature of the earth.

By the way, there are horror stories about geothermal heat pump installations that have gone wrong. It is reported that in one installation, the ground surrounding the heat exchanger froze a very large chunk of the guys yard. Beofre the installation this hadn't happened. The huge ice block slid down a hill and very slowly smashed into the house.

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Listened to the discussion about buying a prius in the US instead of Canada because ya said someting to the effect that you could save 10,000 dollars.

Anyway ever considered that the prius might not be the best way to lower one's environmental footprint or the best economic value, if you look at the "Embodied Energy" and "Life Cycle Analysis."

When I was in college I bought a used diesel benz and it was pretty much my only car for 15 years after I graduated. I would still be using that old benz for running occasional errands, but the car chassis was pretty much rusted out cause for the first few years of that cars life were spent in northern europe.

Instead of blindly going out and buying a prius, which is the fashion fad statement of "environmentalists" here in California as well as many other parts of the world.

In deciding what kind of replacement car I wanted to buy, I first thought about the mission I needed a vehicle to do. Basically I work out of the house and don't have a daily commute, and try and walk most places because it is a form of exercise and in effect has a zero carbon foot print. In the last couple of years I've made a conscious effort to curtail my driving, so now I'm driving less than 4,000 miles around town.

In the end after doing an "Embodied Energy and Life Cycle Analysis" along with consider the local economic factors, ya might find it surprising what came up with as the biggest bang for the buck in terms of the environment and the local economy...... drum roll, a 540 BMW!

Because I don't drive very much, a used 540 BMW turns out to be fit my mission quite nicely. The vehicle was already made so there were no environmental costs in terms of using raw natural resources or energy needed for production or shipping to a dealership. Last year it was driven about 4000 miles, and on long highway trips I can get 25 MPG when I drive a nice steady 55 mph. I keep a fuel log and last year in 2007 I averaged 20.426 MPG which isn't all that bad considering the vehicle itself.

On the economic side, I benefit the local economy by having it serviced at a local shop. Service on a BMW can be expensive, like $200 bucks for an oil change, but I only do that once a year and sice most of that cost is labor, money stays in the local economy.

By buying a used car I also saved myself depreciation costs. For example a brand new prius over time will loose a greater percentage of its value than my used BMW.

The money I saved from buying a new prius, I've invested in the stock market (green investing I might add). Ya talk about green energy on your pod cast, so ya might be interested in an alternative energy ETF that over time I'm pretty sure will increase in value

I looked at this particular "atternative energy" stock ETF because it included a balance of international companies such as wind turbine companies such as

as well as investments in various companies that produce "solar" panels....

anyway back to my main point, the prius might seem like a "green" car, but if ya step back and do some analysis, buying one might not be the best way to save the environment!

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Exactly! Did you do your own life cycle assesment on the BMW? LCA's are very difficult to do but in the end, nothing else matters.

It's difficult to tell what the embodied energy of a battery is. There are many raw materials. The basic input for the NiMH battery that Toyota uses goes something like this: The NiO is mined in northern Ontario, Canada by Inco, gets shipped somewhere in Asia for refinement gets shipped to Japan, made by Panasonic EV, gets integrated into the Prius, then the Prius gets shipped to the US for resale. There's quite a lot of energy in that.

Here's a podcast: /node/97
It's about a life cycle energy study of cars with the conclusion that Hummers consume less energy over their lifetimes than the Prius. This is wrong because they assume a Hummer can go 300k miles and the Prius has a lifetime of 100k miles. I've found some more life-cycle studies that I'll write about soon, but they show hybrids/EV's coming out on top.

But yes, we all must think about the life cycle, not just life. I am struggling with this concept though because if nobody buys a Prius, then Toyota won't put effort into making them easier to manufacture.

Re: theWatt Podcast 73

Hi Ben,

Of course you are right life cycle analysis is more complete than emissions by fuel, however i think that you place to much emphasis on the issue most vehicles will use the large majority of energy during their life rather than manufacture. I`ve seen figuers of 80% impact for fuel but recently heard people state > varies but lets not be to soft on hummers and their VAST resource usage at every stage.

Interestingly LCA also has problems, biofuels make this very clear. A typical LCA of a biofuel will calculate impact based on energy for fertiliser, pesticides, water pumping, sequestration of carbon into soil or erossion and compare this to output of energy. Sounds reasonable. But, another significant factor is land use competition and resultant deforestation, this is typically not included...its not part of a cycle its a one off factor as agricultural trends change but can be hugely significant.

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Having an applied math back ground, I did my best to try and figure out how to maximize use of my money and minimize my environmental impact and it surprises many people when I tell them that a used luxury vehicle like a BMW has less environment impact than if I bought a band new Prius (because I was buying a vehicle was already made and in located in the area vs buying a brand new that had to be manufactured and shipped half way around the world).

I'm listening to this weeks pod cast as I type this, and your guest seems to agree with my analysis that a used vehicle (in my case which I don't drive that much or often) is indeed the best economic and environmental value. Besides, I did check out the Prius and have to say I don't like a few things about the ergonomics of the design: among them are the drivers visibility, the car seats and the handling. In the Prius, with the aerodynamic shape there is the slopped hood that ya cant quite tell where the front of the car ends, and I disliked the lack of the rear ward visibility.

After I bought the BMW to replace my old benz, about a year later I bought a replacement mercedes 300D for my old 300D which I bought when I was at university, because nothing I've ever driven has better visibility (that is because from the drivers seat, it is possible to see exactly where the hood and trunk falls off) or handling in tight urban areas (the steering wheel in the older benz is over sized, kinda like a ships steering wheel), so parallel parking is tight areas is super easy.

The thing that always sucked about my old benz was the seats, I didn't find them all that comfortable, so when I found a low mileage BMW with optional 10-way adjustable sport seats, I told the guy basically as soon as I sat in the BMW, I'm buying this car. I took the BMW out on a closed track, and it accelerates, brakes and handels very nicely, but because it was built a few decades later than than my old benz, there is a sloped hood and trunk for aerodyanamic considerations (but its not as bad from a visibility stand point as the Prius). I also wish the BMW had as much breaking torque as my diesel benz, which basically does not need brakes cause when ya down shift, the car dramatically slows down, the only time ya need to tap the brakes in the benz is when parking, at a stop or in the occasional emergency situation.

All cars are a comprimise of design, including the Prius. In my own case I have various vehicles for various trasnportation missions. Basically I try and use my "keen's"

first and formost because they are IMHO the best all round "green" SUV. I too am kinda torn about wanting new transportation technology like the Prius, but I kind of pick and choose my battles, and look at things as an investment vs looking at something like a consumer. In the end I concluded that the Prius was a consumer good, and the money I saved by opting to buy a used BMW could be invested in the stock market (in companies that produce energy without involving direct buring of fossil fuels).

Having said that I look at cars from an investment point of view, I am kinda interested in buying an urban electric vehicle

Zenn motor cars, has announded they will be producing an AC version of their micro car, which should improve range by 20%.

BTW if ya really want to "struggle with a concept" akin to looking at gas powered V8 BMW as a viable environmental alternative to the Prius, ya might consider that the downturn in the US and global economy due to subprime loans, is actually good for the environment. This is an extension of a wacky counter-intuitive hypothesis about war and the environment.

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At one point while listening I wanted to scream at my computer "It's a heat pump!" Flora valiantly tried to explain how her "geothermal" heating system worked, but I don't think she ever used the words Heat Pump. Just using those 2 words would have helped anyone listening who did not already know how one worked. I'd also recommend NOT using the word "geothermal" with respect to the system, even if the word is all the rage today. It is more properly called a ground source heat pump (versus the more common air source heat pump). The word geothermal brings to mind hot springs and magma and generating renewable electricity from the earth's heat. A ground source heat pump is a completely different concept, and using the word geothermal often confuses people who don't know the distinction. Interestingly, GSHP systems often qualify for "renewable" treatment, although they aren't in any way renewable but rather highly efficient.

And Ben, being from NB, you should know that the Nordic brand of ground source heat pumps are manufactured Petitcodiac,

I think Leslie meant to refer to compressed natural gas (CNG) for cars, not liquified natural gas (LNG). LNG is used for transporting NG via ships, while CNG is what is delivered to your home and is available for filling up your CNG-fuelled car. Liquifying natural gas has an energy penalty - it takes energy to compress the gas down to a liquid - that isn't necessary for automobile use.