AirScape Engineer's Blog

We love railroads. Who can’t love their efficiency. BUT… They like coal. They really like coal. According to this report http://www.aar.org/home/aar2/newsandevents/~/media/aar/railtimeindicators/2010-07-rti.ashx 44% of railroad car traffic is coal. And coal is dirty. It’s dirty in terms of carbon emissions. It’s dirty (but can be cleaned) in terms of particulate emissions. It’s not all that wonderful in terms of mercury dispersal either.

So, which way do you think railroads will lobby (they are corporate “citizens” after all).  Will they throw their weight towards laws which reward efficiency => win for rail transportation. Or will they throw their weight behind more coal burning => still good for railroads.?

Since energy is a topic of conversation in our office, and I have been doing some bicycle commuting, it suddenly became important to have a table of transportation energy use.

Conclusions:

• Bicycle wins the efficiency contest.
• Electric car could win the efficiency contest if you fit 5+ people in your car.
• Escalating that war, the tandem would probably be the next weapon of choice.
• Trains are pretty good (no surprise), and perhaps could get better with regenerative braking.

Assumptions:

• Bicycle uses 50 kcal/mile
• 747 90 mpg (FAA figure is lower,but…)
• Electric car: .25 kwh/mile (from Tesla  if you trust software ‘geniuses’  posing as a car company, or if you trust the old fashioned car company GM, their ‘Volt’ appears to be .34 kW-h/mile)
• <rant> Tesla presents data like a software vendor (no surprise).  Their claim a 70amp @220 volt charger, running for 3.5 hours charges the battery fully (capacity listed as 55kw-h). Energy = efficiency (always less than 1.0) x 70 x 220 x 3.5 = 53.9. Clearly credibility = 1/ efficiency </rant>
• SUV 15 mpg
• Train (swiss) .082kwh/passenger-mile
• Pint of beer has 220 kcal
• kcal (kilocalories) are the kind we eat (aka Calories with a big ‘C’)  Yep, our system of measurement is THAT stupid. Small calories x1000 = Calories =  kilocalories.

Conversion Notes:

• It’s assumed that all liquid fuels have the same energy content as gasoline: 36.6 kwh/ gallon.
• Liquid fuels have crappy energy conversion, unlike electricity which can be 100% efficient.

There are a couple of trends that will affect solar photovoltaic installations:

• Newer electrical rate structures encourage conservation (tiered rates)
• ‘Energy Security’ is a powerful motivator
• Photovoltaic rebates require house efficiency check-ups

We think  solar energy gathering is great. The idea of  getting electricity essentially for  free energy has certainly captivated our imaginations. Even though the cost of photovoltaic panels is dropping very quickly, the investment is still considerable.  Our crystal ball tells us that electrical energy is very, very versatile and will be in demand as electrical cars come on stream and coal fired electrical power plants start to show their ugly side. (coal burning)

As the demand for clean electrical energy increases, its value will certainly not go down.   In fact, if the validity of predicting cheap energy such as the famous line is any guide “too cheap to meter”,then we should get prepared for high prices.

By combining whole house fans solar contractors and  homeowners  can:

• Decrease the initial investment in PV panels
• AND/ OR
• Increase the  Return on Investment for the entire system

The local buddhist temple has just been completed. AirScape provided several whole house fans. The building itself is constructed with ICF (insulated concrete forms). This makes for a high mass, well insulated and sealed building envelope, perfect for whole house fans.  Total airflow from the whole house fans is 9200 CFM – the building is 6,000 sq. feet. That’s a good lot of air, but this is the only form of cooling, so the amount of airflow has to be high for the peak conditions.

If you want to design your own temple, Carlos Delgado is the architect.

This article by Henry Gifford, an energy saving specialist discusses why heat pumps are no panacea.  His points, well made, bring home the messages that building envelope efficiency is critical and the importance of examining the entire energy chain -  from power house to your house.  Not that readers of this blog need reminding, but Henry also points out that over half of this country’s electricity derives from coal burning . (BTW clean coal = oxymoron du jour)

www.energysavingscience.com/

http://www.finehomebuilding.com/departments/taking-issue/heat-pump-schmeat-pump.aspx