SUMMARY

monitoring electricity bill is the heart of a program for efficient management of energy. Bills can not be comparison utility inaccurate information about the amount of savings resulting from programs of energy management proved by the influence of weather and other factors. Correction of current account for weather data provide more accurate representations of economies that are incurred. This article describes why and how weather correction for those that do more with the concepts and methods.

What utility bill THEN CAN DO FOR YOU / Faes> Jim Jefferson County School District wrote to me

is a system of energy accounting is like an airplane on the control panel. To properly navigate your plane, you know where she is, where he was and where it goes. They fly an aircraft without the control panel you have a good chance to crash the plane have. It’s the same thing with energy management. You must know where you are, where you were, where you go, and how, where are you now operates expectations. Their progress />

– Enter the target lane use and costs and their actual performance against goals / br> <- Discover the strong growth of energy consumption and perhaps
take corrective action – the cause of the buildings, the use of more than $ / sq ft than the others, and focus activities of energy management in buildings />
– Make sure you create to be correct by Bill
utility – bills
your tenants (if any) – Whether you have saved your energy from energy saving measures
– aggregates your usage and costs and give them aggregate information to potential energy suppliers
– Create budgets utility

In general, if you look at the condition of your utility to keep accounts, you know where your body and how it is with your goals

FOLLOW bill utilities. The certificate for plant managers and facilities managers
energy and facility managers some, too often to justify their existence to management. How do we save for last year? That is more than what we pay our energy manager? In your recommendations are reasonable refund policy? Why do we even have an energy manager?

There are several ways to determine if your energy conservation efforts of the energy stored as described in the literature, you can place your hands in the air and decide on a figure. Calculate your savings on a data logger and control points, to compare energy bills to determine savings, and ultimately employ building model

(This is called Option A, B, C and D in IPMVP, guidelines and other reference works FEMP). Most likely the easiest and more. method acceptable to the facility manager to determine if option C energy saving, compared to electricity bills. Why? Now, even if the calculations of utility managers present, what they do by the friendly staff of sales, this method is unreliable because they can produce inflated figures. investment data recorders and existing control points seems simple enough, but the transformation of these inputs in number of savings can sometimes be outside the scope of the Skillset manager of the establishment. modeling of the building, then it may be useful, requires hours of time to build the model that can represent and what is the building with the help and can not really represent what the building is actually used. If these objections conclude that the leaves to quantify the electricity bills as the last remaining way to your power as an energy manager. Moreover, in the end it is all about the electric bill is, as the bills reflect how much you pay.

As most facility managers are already tracking their electricity bills, only to see another small step, if you have the energy and money on your program of energy management. Compare bills accounts year last year, saved and you will see, if you have registered.

Now, it’s not so easy. See why.

Why not work the comparison of the bill, or WHY />

There are a few ways that we can use from year to year plot. Let us just looked at the use against time, as do most people.

We have two areas shown in Figure 1 The background (dark) region that we call the use of non-weather sensitive. This use can about computers, lights, pumps at constant volume and other charges that are on any time it is due. For use all year, this amount is constant. (In this case, the use of non-sensitive to weather conditions is very low, since this gauge is a mechanical movement. In general, non-use would be more sensitive to weather.)

We call the upper (lighter) regional weather sensitive use. This is directly related to the use in this case, the air conditioning system. Use in this region can be attributed to refrigeration, cycling chilled water pumps, cooling towers, water pumps, condenser, condenser fans and possible fans and pumps, which are crossed or going on a variable rate.

If last summer was cool, and this summer was hot, then do not use the weather would be sensitive should not change from year to year, but the change of use weather-sensitive. Figure 2 is the same as in Figure 1 except it has two years of data. Notice how the second year, the weather-sensitive part of much larger because of the heat is the cooling load has increased.

Now suppose that the new consumption of chilled water weather sensitive system reduced by 20%. With the change of time in Figure 2, an annual comparison of the use of evidence can not show all the energy savings at all, as shown in Figure 3. (In Figure 3, we see takes 20% of the use of weather-sensitive data for 2002, we have improved perhaps with a chilled water system.)

The management bodies, these results show, after having invested half a million dollars. It is difficult to inspire confidence in the management of graphics, as in Figure 3. So much for the electricity bill comparison. explain

For these results, they could give a picture of DC (as in Figure 4), and then they could see that the post-renovation year (2002) was actually much warmer consumption and necessary cooling and thus an increase. This could be held liable, but you still need to quantify how much you saved, right? Management agrees that the arm waving so long.

You can save your money by updating your current account equation for the weather to quantify. Did you do that you might have presented in Figure 5, Figure 3 instead of

fix works as time rather than comparing the use of last year to use this year, if we use the time correction, we compare the amount of energy that we used to have this year, how much energy we have this year. Many in our industry, without forgetting to use the results of this comparison, savings, use to prevent or cost avoidance. But as we try to keep this paper to an introductory price, we use the word save.

When we tried last year compared with this year of use we saw in Figure 3, and a disastrous project, we used the equation.

save = use last year – this year user>

When we forecast correction, we use end up with Figure 5, and the use of equation:

Savings = How much energy we used this year – the amount of energy we use this year

** * * where this year the The use of an equation is the same as the amount of energy we use this year of 2

equation The next question is how to know how much energy we would have used this year. This is done using the weather correction, as indicated below.

We first choose a year of electricity bills, we look for future use. This would, in general, the year before starting your program of energy efficiency, the year preceding the installation of new managers have been recruited, or a selected year. In this example, we choose the year of user data before the installation of chilled water system. We call this year the base year.

Figure 6, we use basic graphical Year by weather report (in the form of cooling degree days or heating degree days). The blue dots are the electricity bills.

Then there is the line of best fit between the use and weather. The line of best fit is the line that comes closest of all invoices, as shown in Figure 6. We can say that it is the line of best fit are looking for some statistical indicators (like R2-value, net average CVRMSE Bias and error that are not covered in this primer).

The line of best fit has an equation we call the Fit Line Equation, or in this case, the baseline equation. If this equation, we finished with this process of regression.

We want what we did:
– We graphically as a base year relative />

invoices base year. – Best Fit Line = Fit Line />

basic equation = Fit Line Equation

If the basic equation you can determine if you save any energy.

What? You take a bill of law, after a certain period in the base year. You (or your software) in taking the number of days and number of degree days of the change in the basic equation. Remember the basic equation is how your building energy consumption in the base year. While new entries, the number of days and number of heating degree days, the basic equation tells you how much energy is used, the building used this year based on the basic models of Use year and this year the conditions (weather and number of days). We call this use, the use of basic equations, basis.

Now is determined to seek a fair comparison of this year compared to last year, we compare: saving have

= How much energy we would use this year – How much energy we use throughout this year

or added, if we change the terminology a bit:

basic savings = Energy – Actual energy use />

CORRECTION for other variables
facility managers in the industry may want to correct for the production instead of (or more) of meteorological data. It works if you use a simple variable that quantifies your production. For example, a car manufacturer may have produced the track number of the car. If your factory does several things, such as hard drives, desktops, printers and mainframes, it is difficult to achieve a single variable that could amount to produce the overall system. However, if your printer has been served by another unit of a meter or submeter than other units, you can produce the number of printers as a variable for the meter (or submeter), serves the printing unit.

LOCAL CORRECTION IN EXCEL VS. CAN SOFTWARE
time correction can be performed in Excel, but it is difficult, and often can not be as bad as when you have finished using special software. Excel gives regression equations fit line and statistical indicators that show how your usage is represented by the curve fit. However, it is difficult to find the best balance in Excel, how in special software. Excel can force you simply select a point of equilibrium, and then you’d probably go with the balance of different points, while the software keeps you can easily find the line of best fit with different priorities. In addition, if you give your weather data at high or low temperatures average temperatures, it can be difficult, weather data right to the timely implementation of proper accounting. Try it and see.

AVAILABLE LOCAL OFFICE SOFTWARE CORRECTION />

CONCLUSION climate change from year to year. If you want to use utility bills to show energy savings programs for energy management with precision how important it is to fix your electricity bills for climate variations.


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