回到家楼下看到不知哪家订的鲜花快递，突然触动了哪根筋，大哭起来。不走运的时候，果然看什么都悲观起来了。
一进家门，手机显示少年的未接来电。“你到家了吗？我在你楼下了。”
这不是所有姑娘梦寐以求的那句台词嘛！还有什么想不开的呢？
May 14, 2015
#记一件小事 2015/05/14
Trade review 一而再再而三delay，反反复复折腾到了快十点，想着打个车回家直接钻被窝看书，结果叫了出租车迟迟不来，接线员每次都说，就在附近了就在附近了，最后等了四十五分钟也没等到车。一气之下，不坐了！
May 10, 2015
Apr 5, 2015
Mar 15, 2015
Mar 5, 2015
Feb 24, 2015
#Course Review# Energy 101: The Big Picture
This course is provided by Georgia Institute of Technology (via Coursera). The instructor is Dr. Sam Shelton, a nationally recognized expert in energy systems and the founding director of the Georgia Tech Strategic Energy Institute.
Summary of the course:
* US primary energy issues:
1) Carbon emissions;
China and US are the top 2 carbon emission countries: in 2010, China ~ 8000 million metric tons; US ~ 6000 million metric tons (annual emissions).
2) Oil dependence
By 2010, ~60% US oil consumption is imported. US is energy-independent for coal and gas (used for electricity power generation).
* How to solve?
Understand US energy details -> Develop energy technology -> Deploy solutions
Energy flow: Natural fuel -> Conversion process -> Society use
First law of thermodynamics: Energy is conserved. Total energy cannot be created or destroyed.
Second law of thermodynamics: All forms of energy do Not have equal value ("energy quality").
* US energy use
Total energy consumption: Buildings 41%; Manufacturing 31%; Transportation 28%
(US) Energy consumption and GDP are highly correlated.
US oil price is set by world supply and demand.
US oil consumption by sector: Transportation 72%; Manufacturing 23%
How to reduce carbon emission?
- Solar / Wind / Nuclear electric power generation
- High MPH vehicles
- Ethanol fuel for transportation
- Higher efficiency electric heating / air conditioning
In US, wind power density variation from region to region: a factor of 10
For solar, it is only a factor of 2 (more uniform nationwide)
US total energy source:
Coal > Natural Gas > Oil > Nuclear > Biomass > Hydro > Wind > Geothermal > Solar
Energy policy should be based on fact, not industry lobby.
Summary of the course:
* US primary energy issues:
1) Carbon emissions;
China and US are the top 2 carbon emission countries: in 2010, China ~ 8000 million metric tons; US ~ 6000 million metric tons (annual emissions).
2) Oil dependence
By 2010, ~60% US oil consumption is imported. US is energy-independent for coal and gas (used for electricity power generation).
* How to solve?
Understand US energy details -> Develop energy technology -> Deploy solutions
Energy flow: Natural fuel -> Conversion process -> Society use
First law of thermodynamics: Energy is conserved. Total energy cannot be created or destroyed.
Second law of thermodynamics: All forms of energy do Not have equal value ("energy quality").
* US energy use
Total energy consumption: Buildings 41%; Manufacturing 31%; Transportation 28%
(US) Energy consumption and GDP are highly correlated.
US oil price is set by world supply and demand.
US Oil Trend
US oil consumption by sector: Transportation 72%; Manufacturing 23%
Oil vs Petroleum: petroleum includes oil, natural gas liquids and ethanol
- Solar / Wind / Nuclear electric power generation
- High MPH vehicles
- Ethanol fuel for transportation
- Higher efficiency electric heating / air conditioning
In US, wind power density variation from region to region: a factor of 10
For solar, it is only a factor of 2 (more uniform nationwide)
US total energy source:
Coal > Natural Gas > Oil > Nuclear > Biomass > Hydro > Wind > Geothermal > Solar
Energy policy should be based on fact, not industry lobby.
Feb 23, 2015
Subscribe to:
Posts (Atom)