Utility Bill Analysis Charlie Richardson Longs Peak EC Boulder, CO

Session Objective: Before you leave this session, you will believe and understand that utility bill analysis is every bit as essential of an energy auditing tool as any piece of equipment you carry into a house in your toolbox.

Modeling energy conservation My solution to winter, layering! 20+ years in WAP Manage and audit Train auditors & techs I use UBA every day It works!

Where I’m from

Saturday morning Colorado Tourism Councils says “please come ski”

Then, please go back home

Boulder, Colorado Predominantly heating climate, with some cooling degree days Predominantly individually heated single family homes, mobile homes, townhomes Natural gas used primarily for heating and DHW, electricity for appliances and some air conditioning.

Why analyze utility bills? Predict savings potential of job Match tools to job Making a smarter, better energy auditor

Savings follows waste! You can’t save what isn’t being consumed Energy evaluations show that high energy consumption is one of the best predictors of savings Every home uses energy differently Your customer looks to you to tell them how they can save energy - you’re the expert!

The right tool for the job

Match tools to the job Some homes don’t need a crew Some homes need your best crew Knowing which is which in advance is more efficient way to operate

Making a better auditor You look smarter when you are prepared (you are smarter) Time is valuable (yours and the homeowner’s) You will become a better auditor!

And, let’s face it: You probably don’t look this good To spend… Four hours… Doing an audit.

But, someday, you could…. look like this:

Making connections How many oranges does it take?

Get to know your neighborhood How many Btus do we see? 100 1,000 10, ,000 1,000,000?

Home Heating Index Btu/sq.ft./heating degree days Easy scale to work with, remember and get your (and homeowner’s) mind around. Generally runs from in SF homes Most conventionally built homes won’t get below 2 without alternative heating sources, radical shell improvements, or heroic conservation efforts Most homes, well retrofit, have chance to achieve HHI of 3 to 4

The math (sample): 12 months gas (for heating) = 1000 therms Btus = 1,000 x 100,000 = 100 million Square footage = 2000 Heating Degree Days = 5000 Home Heating Index calculation: 100 million(btu)/2000 (sq.ft.)/5000(HDD) = 10 btu/sqft/heating degree days

“Random” sampling HHI Average HHI of this sample = 5.3 btu/sqft/hdd

What other connections are meaningful? Domestic hot water consumption per month Baseload electric, kWh per day or month Annual electric, kWh Annual gas, therms Summer cooling load, kWh What ever you can compare to other houses to get meaningful information about how house or household is using energy

People want to know… Where they rank In energy use In energy cost

Making connections: Recognizing the “low hanging fruit” and how to harvest it immediately. Recognizing the excess consumption and how to trim with the right tools. Every home has a bottom line of energy use. Learn what that is!

Pick low hanging fruit

Trim the excess After picking the fruit, there’s still work Low infiltration Good insulation Efficient systems Efficient appliances Smart users

Getting down to the trunk Some energy use is required for the basics. You can’t go below that

What is the lower limit? Work your way backwards: HHI3 HDD5500 DHW (base)10 Size of homeAnnual fuel use: Square FeetThermsMMBTUkWhGal. PropaneCord Wood Heating oil ?etc ?etc ? ? ? ? ? ? ?

UBA in Colorado Colorado Wx Agencies receive training on Excel based UBA spreadsheet Boulder REAP program uses UBA to prepare auditors for residential home energy audits ConservEd Program, Synertech Systems, utilities, others working on analysis systems

Sample graph of gas use

Sample graph of electric use

Simple is good…

Comparisons are useful…

With enough data, you can start to tell a story

Change Is not always easy to make

We’re set in our ways… What are you driving these days?

Still not convinced? Look at costs on completed jobs and compare to historical energy usage of those homes.

How to get started? Understand your data sets Develop relationship with data sources - customers, utility companies, etc. Get familiar with bills, billing methods, utility history reports Begin to formulate what information can be derived from the histories, and how to get it

Find a local spreadsheet geek, Or become one, Like me!!!