Engineering Principles

This chapter reviews and reinforces the fundamental themes of the book.

21.2 GENERAL PRINCIPLES OF ENERGY CONSERVATION.

The easiest way to save energy is “don’t use the appliance.” There are several variations on this theme.

• Turn it off.
• Put it on a timer.
• Install a programmable controller. • Control it with a smartphone app.
• Do it the old-fashioned way, by hand, without technology.

21.3 A FEW BASIC ENGINEERING PRINCIPLES EXPLAIN MOST  OF THE IDEAS.

• Simple is better.
• You count calories and miles per gallon. Now learn to count watts.
• The larger the temperature difference, the more insulation you need.
• It’s probably still using electricity even when it’s turned off.
• Diligent attention to lowering your heating and cooling demand means when you buy a new furnace or AC, it will be smaller and less costly.
• Heat rises.
• If it has a motherboard, every repair costs a fortune.
• You’ll be more diligent in doing an “energy tip” if you understand a little bit about how and why it works.
• Be afraid of electricity. Be terrified of 240-volt electricity.
• Humidity wants to equalize across all barriers. It never stops trying.
• If you understand the science, you won’t have to remember a long list of tips but just practice the one, basic principle at work.
• The greater the temperature difference across a wall, the more heat flows.
• The longer it operates, the more money you save by replacing it.
• What matters is how often you use the device or fixture. If the energy-hog bulb is only on five minutes a day twice a month, don’t worry about it.
• It’s okay to try things that are within your skillset. If you screw up, you can always hire a contractor to fix it (and learn how to do it right the next time).

21.4 THERE ARE PLENTY OF WAYS TO SAVE ENERGY WITHOUT  SPENDING A PENNY. 

With very few exceptions, the only time to make a major purchase is when your old equipment has failed and is beyond repair.

The “experts” always advise you to purchase a newer, more efficient appliance.

Do you really need a new one? How many more years can you get out of what you have now?

Can you refurbish the old one? Paint the car fire-engine red, rebuild the heat pump, or install a new refrigerator compressor that isn’t so damn loud.

Will you use this fancy, new machine as designed?

Would you be more comfortable keeping what you have now? It’s safe, dependable, and you know how to repair it. The family wheels are already beat up; you don’t worry about every new scratch and ding.

21.5 JUST BECAUSE IT’S A NEW MODEL DOESN’T MEAN IT  SAVES ENOUGH ENERGY TO JUSTIFY THE PURCHASE. 

Engineers’ entire job is to make things more energy-efficient. That’s all we do, without exception.

Every new model is more efficient than the last one. That’s why it’s a “new model.”

New models often have fewer features. No spare tire? No CD player? Not certified for towing? I can’t turn off the touch screen? Premium gas only? The back windows don’t roll down?

 21.6 IF YOU’RE SPENDING HARD CASH, DON’T LET EMOTIONS  INFLUENCE YOUR DECISION.

Everybody is a used-car salesman.

If you’re not sure it’s worth the money, you’re probably right. (This book finetunes that sixth sense into a killer instinct.)

Don’t let them use your desire to use less energy, go green, or save the planet to close the deal.

The more research you do, the better your decision.

The more the salesman sees you know, the better the deal you can wrangle.

 21.7 THINK ABOUT YOUR NEW PURCHASE AS A BUSINESS  TRANSACTION.

If they tell you it saves energy, ask, “How much?” It always saves less energy than they say it will.

You can prove anything with statics.

Real-life “case studies” aren’t worth a damn unless the data is customized to your exact situation.

 “All the sunshine we get around here, how can solar panels not work?” Have you considered the annual sun-hours, the shading of my house from large trees, the orientation of my roof, cloud cover, air pollution, and expected snow cover? “Call me when you have the numbers.”

 21.8 ALWAYS CALCULATE PAYBACK.

High-dollar energy conservation projects can be straightforward to prove—if you’re terrified of numbers.

Always ask, “How much energy will it save?”

Ask the salesman to find the energy savings per year, in dollars, using your exact utility rate.

Calculate the payback = purchase price divided by annual dollar savings.

The longer the lifetime of the project, the longer the allowable payback for your energy-conservation budget.

The maximum payback should be three to five years. No exceptions.

New windows are a favorite project. They cost, on average, $8,000 and save 5 percent off the average $2,000/year utility bill. That’s a payback of eighty years! Not good.

Payback is the number of years it takes to pay off your investment out of the energy savings.

You don’t save any money until the payback period is complete.

 21.9 LOOK FOR REBATES ON EVERY LARGE PURCHASE.

Many entities offer rebates: manufacturers, utilities, state and local governments, and the federal government via tax credits on your earned income.

Rebates lower the cost and improve the payback.

Sometimes you can donate old appliances to a charity (refrigerators, washers, dryers, even cars) for a tax credit.

Any part of the project you can do yourself lowers the cost (painting, caulking, adding insulation, weatherization, yard work).

EnergyStar.gov has a “Rebate Finder” that lists all available rebates in your area, for various appliances.

 21.10 CONSIDERATIONS IN THE TIME–VALUE OF YOUR INVESTMENT.

An insistence on calculating the payback is critical to every energy conservation decision. Time is a crucial factor.

If you will not be in the house five years from now, don’t make any improvements unless the equipment breaks down, and then don’t spend more than you absolutely have to.

Appraisers don’t give your house any extra value for energy-efficiency. All they care about is if it works.

If you do make that big-dollar purchase, make sure you bring it with you when you move (refrigerator, washer, dryer).

When you get an appraisal, be sure to point out all your energy improvements.

Maybe your realtor can ask the buyer for an allowance to the asking price.

 21.11 KEEP TRACK OF YOUR ENERGY USAGE.

It’s helpful to quantify your energy-saving activities. Visuals give valuable feedback on your progress and reinforce your green enthusiasm.

Large utilities offer a monthly progress report, comparing your electricity usage to similar homes in the area. My utility sends a colorful email with a twelve-month graph of average homes versus efficient homes versus my house.

Ask your utility to install a “smart meter,” and you can log into your account online for a daily plot of your power usage versus the outside temperature.

Or you can read your meter once a day and plot it. Later I list a few smartphone apps that graph utility data for you.

Weather and household activities are variable month to month. It may be a few months before you see a noticeable trend resulting from your energy-cutting activities.

Most energy tips related to the house are regular maintenance items that maintain the value of your home and protect it from, for example, water or termite damage.

 21.12 THE BEST WAY TO PROMOTE ENERGY CONSERVATION IS  TO INCREASE THE COST OF ENERGY. 

That’s the official position. (Sometimes I get on a soapbox.)

Higher prices are easy to implement with a point-of-use tax. They’re efficient, with little administrative overhead—and they work.

Of course, they work. When gas is $5 a gallon, people drive less, take fewer long-distance trips, and purchase more efficient vehicles.

Higher energy prices are easy-money for the government, corporations, and stockholders.

Higher energy prices are also a regressive tax that puts the most onerous burden on those who spend the highest percentage of their income on energy: the poor.

Note: This thread isn’t off-topic. I have a whole chapter devoted to automotive tips.

21.13 WE DO NEED AN ADDITIONAL $1 FEDERAL TAX ON GASOLINE. 

(Sometimes it takes a little while before I get to the point.)

The American Society of Civil Engineers gives the nation’s roads a “D” grade and bridges a C+.

We need additional revenue to upgrade deteriorating roads nationwide. Bridges have an expected lifetime of fifty years. Their average age is forty-five years—and counting!

Heavy trucks cause 99 percent of the damage to our roads but pay only one third of the taxes.

Europeans pay an average of $8 a gallon for gas, versus $2.50 in the United States.

Most American auto manufacturers have a full line of models they sell overseas

(smaller, cheaper, more energy-efficient). Those models aren’t sold in the United States. Why? Because much smaller equals much lower profits.

Also, those vehicles aren’t designed for the terrible roads as we have in America.

So, we’re stuck with the big, ugly gas-guzzlers.

 21.14 UTILITIES HAVE, FOR DECADES, LEVIED HIGHER PRICES

ON COMMERCIAL users to force businesses to shift their electricity demand outside of peak-use hours.

Peak demand charges penalize commercial accounts for their highest fifteen minute energy use on any given day.

The incentive: up to 50 percent cheaper electricity outside of peak hours (typically 4-6 P.M.) and weekday business hours in general.

Fifteen percent of the utilities in the United States have these “time of use” rates for residential users.

The utility must upgrade your electricity meter to a “smart meter” (which tracks usage in real-time) to qualify you for these new rates.

“Smart meters” save money for the utilities, too. They can read your usage remotely, detect outages right away, and troubleshoot problems better.

 21.15 SOMETIMES, ENGINEERING GETS POLITICAL.

The highest obligation of any Professional Engineer (PE) is to protect the public health.

Civil PEs are concerned for the safety of drivers on bad roadways and bridges.

Energy engineers worry because crummy roads motivate drivers toward tough, heavy pickups and SUVs. Small, fuel-efficient vehicles are unsafe, problematic, and suffer more mechanical road-related issues.

If gasoline becomes too expensive, people fly more often, which is even more damaging to the environment.

 21.16 FUTURE TECH!

Every chapter concludes with futuristic ideas to make things more energy efficient, often involving changes to codes, regulations, or federal policy.

All households should qualify for “time of use” rates. This book explains many ways to take advantage of the 50 percent lower off-peak cost. If you have that rate, it cuts the payback time in half for most projects.

Rebates from utilities for high-dollar projects should require a thorough payback analysis by the contractor before the project is approved.

Railroads are the cheapest way to move goods overland. A higher tax on shipping companies encourages shippers to shift their heaviest traffic from trucks to trains.

A tax on gasoline at the refinery level increases the price per gallon for everybody. A standard $5,000 federal tax credit to all drivers lessens the burden on low income drivers and make the tax non-regressive.

A per-mile tax on luxury vehicles, heavy pickups, and SUVs paid each year when you get a vehicle inspected sends money at the county level for road maintenance.

Credit card companies should reward “frequent railroad miles” instead of frequent flyer miles.

A federal tax credit for planting trees. If you don’t have a house with land, or a house at all, your neighborhood can ban together and “Adopt a Highway” to plant trees there.

Renew the federal tax deduction for “energy efficiency improvements” to you house. You can still deduct solar photovoltaics but not adding attic insulation and other improvements.