Who talks more? Men or Women? Making Electricity from Car Exhaust and Geothermal Energy in the Home

February 20

This week we address the controversial issue of who talks more. Men or Women? I know many of you will have opinions but does the science back up your opinion? We discover a new device that can be retrofitted to your car to generate electricity from your exhaust pipe. We investigate a startup that is making access to geothermal energy cheaper for the home and finally we examine a new Cement Quality Test. I know that some of you love stories about concrete.

Who Talks More? Men or Women?

This is a controversial subject for some but there is science that we apply to this question. The stereotype is that women are more verbose and that men are succinct and precise in their communications. A 2007 study from the University of Arizona found that men and women spoke about the same number of words per day, roughly 16,000.

The study however was flawed. It only used undergraduate students in Austin Texas as test subjects. A new larger follow up study from the same researchers has painted a more nuanced landscape.

The new study found that women between the ages of 25 and 65 spoke on average 3,000 words a day more than similarly aged males. However the gender differences did not appear in the 10 to 17, 18 to 24 and 65 and up age groups.

The initial study only covered 500 students. The students wore a portable recording device (EAR) that turned on at random intervals to capture snippets of daily conversation. This allowed an estimate of daily speaking. The new follow up study analyzed 630,000 EAR recordings from 22 studies on four continents with 2,197 participants. The new study participants ranged from 10 years old to 94.

The only gender difference was women from 25 to 64 spoke an average of 21,845 words per day, men spoke 18,750.Interestingly both genders have tended to speak roughly 300 words a day less in the later studies than they did in 2007. Our devices are likely taking over our communications.

Additionally there is significant variation in the amount of words spoken by individuals of both genders. The quietest participant was a male who spoke an average of 100 words per day. The most verbose participant was also male. He spoke more than 120,000 words per day (I think I might know this guy).

Turn your Car Exhaust into Electricity

Internal Combustion Engines only use one quarter to a half of their fuel’s potential energy. The rest is lost as heat mostly through exhaust pipes. A team of researchers from Pensilvania State University have developed a new device that attaches to your exhaust pipe and turns waste heat into electricity.

There are some current devices that can do a similar job however they are heavy and complex, requiring additional cooling systems to operate. This new device will work on cars, helicopters and unmanned aerial vehicles.

The new thermoelectric generator contains a semiconductor made of bismuth-telluride and uses heat exchangers to capture the heat from the exhaust pipes. A heatsink regulates the temperature. The heatsink increases the temperature difference between parts of the device which increases the electrical output.

In simulations of high speed movement (driving on a freeway etc.) the system produced up to 56 Watts for car like exhaust systems. This is the equivalent of five lithium 18650 batteries (a small battery that is used in doorbells and other devices).

The system can be retrofitted to the exhaust pipe of current model cars and be used to generate power for use elsewhere in the car. Newer hybrid cars may have this type of system added to assist in power regeneration. Every little bit helps.

Geothermal Energy in the Home

Swiss startup Borobotics has developed a simple way to tap into the Earth’s heat as an energy source for the home. Nicknamed “Grabowski”(after a mole made famous by Slovenian author Louis Murschetz) the device is 13.5 centimeters wide and 2.8 meters long. It drills almost anywhere to bring heat to the house.

In many European countries the average temperature at a depth of 250 meters is 14 degrees. This is an ideal temperature for heating in winter and cooling in summer. The device has the capability to drill to 500 meters deep which makes it ideal for a home heat pump.

The drill is compact enough to be able to operate in small garden, parking garage or basement. The drill is autonomous and is plugged into a standard electrical outlet. Grabowski’s head can detect what it is drilling into. If it encounters water or gas pipes it will automatically seal the hole and start again.

Grabowski is 84% smaller than current drills, 36% cheaper and reduces the noise of drilling by 94%. Geothermal heat is always available and free to use. The EU has committed to install 43 million new heat pumps before 2030.

Cement Quality Test

A team at the University of Illinois has developed a new type of test that can predict the performance of a new type of cementitious construction material in five minutes. The current industry standard test takes seven days. This new test may speed up the use of next generation resourses called supplementary cementitious materials (SCMs).

Newer SCMs like calcined clays can partially replace ordinary cement and make durable low cost concrete that produces less carbon dioxide during production. The new test uses a low cost analysis called colorimetry and camera technology for real time quality control of calcined clays. Calcined clays are SCMs that contain aluminum and silicon containing materials that become chemically reactive when heated to 600 to 900 degrees C.

After heating the aluminum and silicon in the calcined clays become chemically reactive which allows them to contribute to the long term strengthening in mortar and concrete. The level of reactivity is measured and is used to predict the product’s final strength. This allows real time quality control.

Increasing concentrations of aluminum and silicon in the clay’s solution result in increasing amounts of pink and blue. A cheap camera is used to photograph the solution and the corresponding Red Green Blue values in the image is compared to an established calibration curve. This gives comparable results to the current industry standard seven day test.

The test has only been used on the new SCMs. A wide range of other supplementary cementitious materials are under development. The team hopes to be able to test their system on these new materials as they are developed.

Paying it Forward

If you have a start-up or know of a start-up that has a product ready for market please let me know. I would be happy to have a look and feature the startup in this newsletter. Also if any startups need introductions please get in touch and I will help where I can.

If you have any questions or comments please comment below.

I would also appreciate it if you could forward this newsletter to anyone that you think might be interested or provide a recommendation on Substack.