Calculate Renewable Energy Requirements

Regardless how you feel about the issue, most people would agree that the Copenhagen Climate Conference certainly didn’t resolve very much.  But don’t worry – this post isn’t going to inundate you with more vague talk about climate change and energy independence1 – rather, it’s going to be introduce a fun, FREE, book:

Have you heard about Sustainable Energy – Without Hot Air by David JC MacKay? You can buy it or read it free online. It takes a fresh, numerical look at sustainable energy: trying to actually put numbers to today’s problems and see what ideas really add up, instead of relying on adjectives and weasel-words. For any of the hot topics flying around these days: energy independence, global warming, peak oil, etc., I’d recommend this book. It provides a bit of fact-checking reality, whether you are for or against mandating renewable power. It’s also got a sense of humour.

The book sets itself a goal: let us see if Britain (his country) really can sustain itself on renewable energy, using back-of-the-envelope calculations and real numbers from literature. Is it even technically feasible?? To test our chances, MacKay suggests we try a thought experiment: we will assume Britain can do energy projects on absolutely massive scales without public protests, let all economic concerns fade into the background, and convert all forms of energy production and energy use into one simple unit: the kwh/D. Then we will tally up the consumption, estimate how much production we could actually get going with renewables, and see what happens. Continue reading

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  1. Although trust me, I could go on forever if I wanted to. []
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Posted in Environment / Climate Change, Renewable Energy / Conservation | Tagged , , , , , | 1 Comment

Microsoft Patch Causing Blue Screen of Death

This beset a few people I know:

KB977165 (aka MS10-015) is causing some people to get the blue screen of death.

A solution for some, which did not work for me: http://www.krebsonsecurity.com/2010/02/new-patches-cause-bsod-for-some-windows-xp-users/

Edit: Microsoft has withdrawn the patch for now. Should be safe to update.

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Use VLOOKUP and HLOOKUP to use Data Tables in Calculations

Small Excel tip today: use the Excel functions VLOOKUP and HLOOKUP to allow you to use tables of data in your calculations. You can configure these commands to “look for the closest match” or to “only find an exact match” by setting the final argument in the functions to TRUE or to FALSE.

When could this help you? Any time you’d like to automate the reading of a table of information. Or any time you can put the action you want to perform into a table form. Or, any time looking in a table of values suits better than trying to use an equation or curve-fit to predict the values.

Using VLOOKUP in a calculation or list

I have 100 items to enter into this cost estimation. If I have to lookup the material multiplier each time, I'll make a mistake. Or I'll go crazy. Lets use VLOOKUP instead!

Here are some ideas to use these functions:

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Posted in Excel | Tagged , , , , , | 1 Comment

Consider Finned Tubes to Increase Surface Area

This post will introduce the practice of adding fins to shell-and-tube heat exchanger tubes to increase the surface area, and discuss when to consider it and when to avoid it. This is not a post about air coolers.

Image of finned tubes: Heft Engineers Website

Review: When fluid flows through tubes in a heat exchanger, the total resistance to heat exchange is the sum of: tubeside fluid convection resistance, tube material conduction resistance, shellside fluid convection resistance. Often there is fouling, which will add tubeside and/or shellside fouling conduction resistance. The shell-side fluid resistance is governed by the equation:

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Posted in Fired Heaters, Heat Exchange | Tagged , , , , | 3 Comments

Salary Comparison & Prediction Tools

It’s a new year, and maybe time for new jobs! Or at least performance reviews. Knowing your “fair salary,” or the “going market rate” that is paid for your position, can be very helpful. It’s also great to know when you’re a student graduating into your first real job.

Salary Negotiations

Salary Negotiations by Mike "Dakinewavamon" Kline CC by 2.0

It’s a tricky subject, dependant on factors like your profession, location, your specific experiences, how much the interviewer likes your jacket, broad economic and demographic trends, the rigours and demands of the position you are applying to, and frankly–luck.

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Posted in Career Advice | Tagged , , , , | 1 Comment