Solar-Electric Cars vs Biofuel Cars

It seems obvious to a person or decent scientific intellect like myself that solar-electric cars are more efficient than bio-fuel cars; however, the significant part of a recent study (click here for original) that determined that electricity generated by solar is more efficient than bio-fuels for powering cars is that the analysis considered many factors of material or resource use in addition to pollution. The factors were:

• Land-use
• Greenhouse gas emissions
• Fossil fuel use
• The production and use life cycles of the fuel
• The production and use life cycles of the vehicle

The report was done by a team that compared 5 different approaches to power a compact passenger vehicle for 100 kilometers.

• Battery-electric vehicles (BEVs) run on electricity from solar power.
• Battery-electric vehicles run on electricity from switchgrass.
• Internal combustion vehicles (ICVs) run on switchgrass biofuel.
• Battery-electric vehicles run on electricity from corn.
• Internal combustion vehicles run on corn-based biofuel.

In terms of land-use, the report says that solar significantly out-performed all other options – it doesn’t require farm land. It performed modestly better than switchgrass in terms of greenhouse gas emissions, and significantly better than corn-based biofuel. Solar was actually equal or slightly worse than switchgrass when it came to fossil fuel requirements over the totality of the life cycle, but it still out-performed corn-based internal combustion.

Solar Electic Cars vs Biofuel Cars

The central bottleneck, as the report notes, is the low efficiency of photosynthesis. Biofuels and bioelectricity use photosynthesis to convert solar radiation into energy for transportation services. While photosynthesis has a theoretical maximum energy conversion efficiency of 33%, the overall conversion efficiency of sunlight into terrestrial biomass is typically below 1%, regardless of crop type and growing conditions. Modern, thin-film PV converts sunlight to electricity at 10%. It is believed that less than 1% of global land areas would be needed to supply all the world’s electricity needs in 2050.

Traditional corn-based biofuels are problematic because carbon emissions from agricultural production over their full life cycle largely wipe out any carbon benefits at the point of actual vehicle use. And new cropland sequesters less carbon from the atmosphere than the grassland or forest it typically displaces. Switchgrass and other cellulosic biofuel are not immune to these other flaws either.

The Devil’s Advocate
There are still a number of variables and perspectives missing from this ra-ra-ra report for solar-electric.

1) For me, a significant consideration that is missing is the commercial viability, as in what is the cost and efficiency-rating of building a new infrastructure? One would assume “less” but science is not about assumptions. This study is missing that.

2) Cost of infrastructure development is projecting and a little bit beyond the scope of this study, so that might not be fair. I propose that there is another variable that is missing: cost. Prices are conveniently left out of this study. In my novitiate opinion, price or ‘cost of goods sold’ is directly proportional to resource usage.

3) The report/study did not consider other circumstances such as region or weather and cyclical demand (daily, weekly, seasonally, yearly).

4) The report/study doesn’t consider nuclear energy generation.

In the end, we all want things to better. Better studies need to be done and questions always need to be asked. Hold their feet to the fire… even scientists!

Posted in Auto, Biofuel, Energy, Lifestyle, Reduce, Solar, Transportation | Leave a comment

A Neat & Efficient House Design

The article below is about a fantastic home design about a home that follows the sun to maximize solar efficiency. All that is takes to rotate this home is 28 wheels, two motors, and less power use than a light bulb.

Energy Efficient Rotating House Concept

Artist impressions of the rotating house to be built in Crace, ACT, Australia.

Dubbed Girasole for its ability to follow the sun, the four-bedroom home in northern Canberra has been designed by DNA Architects and Industrious Design. The new design schema will allow the home to take full advantage of natural light and solar efficiency. The house will be able to track the sun automatically and complete a full rotation in less than 10 minutes. Furthermore, the eco-friendly, single-story home includes a sloping roof with 10,500-kilowatt solar panels that are able to generate enough energy to power the home and its hot water system.

Builder and owner of MAG Constructions John Andriolo said, “Girasole will encourage a change in thinking away from needing to find a perfectly oriented block and will demonstrate that even the most ambitious undertakings can be seen as a prototype for future environmentally friendly homes.” The design took several months and was a significant change from the company’s usual work with rail. There were several safety elements involved in the design, which has no overhang and features fixed components such as the walkway and veranda. Only the home itself rotates, which has a 120,000-litre water tank beneath the 704-square-metre block.

Due to the lack of lifting involved in the process, the rotation uses minimal energy – about 100 watts, which is about the same as a bright light bulb. Although rotating homes were likely to remain a niche market, the eco-friendly design could inspire other projects. “It’s never going to be the main type of houses people design, but it has its benefits,” John said. “You may see more of these homes out there.”

Despite the unique design, the planning process for Girasole was relatively normal. There were some initial concerns regarding privacy – the house faces either the street or the backyard for most of the year.

The house is expected to be on the market by February 2013.

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Energy Efficient Rotating House Site LayoutEnergy Efficient Rotating HouseEnergy Efficient Rotating House Builder John Andriolo

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Golf Mat to Practice Chipping

I play golf. Yes, I know it is a very indulgent and water-wasteful sport. Actually it pollutes a lot too by way of fertilizers and emissions, which can easily be deduced my the mere cost of playing a round of golf or even hitting golf balls at a driving range. It’s getting better… I hope.

Anywho, I like to practice my chipping in the backyard by trying to land shots in a bucket. The activity was ruining significant swath of grass. That’s not the best thing to do to one’s unnaturally green lawn here in the desert (I rent. If I owned, I would zero-scape). Plus, I was not able to chip or pitch off of clean or even tight lies. For the last couple of weeks, I had been scouring the occasional thrift store and Craiglist for a piece of synthetic turf that I could set on the ground and move around the yard or driveway. No luck.

Then, the other day, I looked down and there it was, my wife’s fancy Chilewich outdoor welcoming mat. It was perfect… moveable, durable and provided a nice neat/tight lie. Bingo! It’s held up after a week of practice (5-10 min a day) from 5 to 30 yards. I don’t take much for divots on the longer pitches, so it should last. If it does start to see some wear, I’ll blame it on the bitch (our dog).

For you, I doubt one would need an over-priced floor mat ($45) to get the same result. I’m guessing you could find a good synthetic floor mat at Walmart for a few bucks or used one at a garage sale for $1.

Posted in Health, Physical, Reuse, Save Money, Shopping, Water | Leave a comment