November 19, 2007

New 'FatBox' Device Produces Biodiesel from Solid Animal Fats

ConocoPhillips and Tyson have an agreement to convert Tyson's pork, beef, and chicken fat into diesel fuel. They will use a hydrotreating process and blend it with normal diesel production. As I recall, all of Tyson's fat will yield only 15,000 barrels/day of diesel...a drop in the bucket but every little bit helps.

October 24, 2007

What's the Difference Between Solar Energy and Solar Power?

Solar power and energy are used almost synonymously by the press and general public. But to an engineer they are distinctly different. Power is the capability to do work, and energy is the quantity of work done. For example, the quantity of energy created by a generator with a power rating of 10 KW is the connected load (which can range from 0 to 10KW) multiplied times the time the generator runs in hours to give kw-hours. Power is measured in kw and energy is measured in kw-hrs. A PV array is solar powered (the array has a kw rating) but collects solar energy measured by a meter that multiplies powerXtime and accumulates kw-hrs. If you are still confused, don't worry, you have lots of company.

October 25, 2007

What's the Difference Between Solar Energy and Solar Power?

I wanted to avoid higher math but you are right Mr. Breza. Energy=Work = the integral of dP X dT. In a PV array the power=watts=(volts X amps) none of which are constant due to cloud passage, shading, and sun angle. The integration of instantaneous power (watts) X delta time (hours) is done in the kw-hour meter to give the amount of energy produced. Mr. New has the right equation Power=Work/Time or transposed Work=Power X Time, but then he mixes units. Enough said.

October 25, 2007

What's the Difference Between Solar Energy and Solar Power?

Correction: Energy=Work = the integral of P X dT.

October 17, 2007

Poll Shows Overwhelming Support for Renewable Fuel Options

In the early 1800's when the norhteast relied on biofuels for the economy, the land was clearcut of all trees leaving no primordal forest. Take a look at paintings from the period. My family ancestors had a thriving charcoal business. With the advent of oil, re-forestation began. History says biofuels can help, but they are not the answer, we are too energy hungry.

October 10, 2007

Texas Decision Could Double Wind Power Capacity in the U.S.

I agree with you, Greg. I've been puzzled by some of the acronyms. I'm an editorial judge for an engineering magazine and proper writing etiquette is to spell out what you are saying the first time followed by the acronym in parentheses. Then the acronym can be freely used, e.g. compressed air energy storage (CAES).

October 05, 2007

Mass Market for Green Homes Coming?

Its nice to see a century old idea come of age. Thomas Edison had the idea of concrete prefabs in 1908 and many are still standing and inhabited in New Jersey. Like solar, it takes a while to catch on.

September 19, 2007

Why Don't We Hear Much About Anaerobic Digestion in the U.S.?

Might the whole process be more efficient and cheaper to just dry the biomass in the sun and burn it directly as fuel as the first settlers moving west did? They used dried cow chips for cooking and heating. Does anyone have data on this?

August 29, 2007

Wind Data Offers Some Surprises

In my work I find that even engineers cannot keep units of power and energy straight. It can lead to gross errors in calculating the dollar value of the energy produced by generating equipment.

August 29, 2007

German Biodiesel Industry Peaks, Trouble Ahead

This is a tribute to the inefficiency of government. Spend millions on subsidies and research grants to promote a tecnology and then kill it with taxes.

August 10, 2007