Ivy Resident Support Center

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Understanding Estimated Bills

At Ivy, we aim to make your billing experience smooth, transparent, and accurate. Occasionally, we may need to estimate your energy usage to ensure you receive your bill on time. This article explains why this happens, how we calculate estimates, and what happens once your actual data becomes available.

When does Ivy estimate my bill?

Ivy calculates your Solar Statement each month using actual consumption data from your utility provider. If this data isn’t available by the time Ivy needs to produce your Solar Statement, we estimate your energy usage to ensure you receive your bill on time.

Our estimation process is designed to be as accurate as possible. If there are any differences between the estimate and your actual energy usage, we’ll correct this through a process called a “True-Up” once your data becomes available.

Why is my data missing?

There are a few reasons why your energy usage data might not be available when it’s time to generate your bill. These situations are typically out of Ivy’s control and can include:

Utility provider delays: Utility providers may experience technical issues that delay the transfer of data to Ivy.

Lost authorization: If Ivy loses access to your utility account, you’ll need to reconnect it to restore access to your data.

Utility bill corrections: Occasionally, utility providers restrict access to data while making corrections to past bills.

How does Ivy estimate my bill?

Ivy estimates your gross energy consumption. This data shows how much energy your unit consumes in 15-minute intervals throughout the billing period.

Your gross energy consumption is the basis for how Ivy calculates “What I Would Have Paid Without Solar” section of the Solar Statement. This data represents how much energy you consume in a billing period and the time of day you used it. For example, if you’re on a Time-of-Use rate, energy costs vary depending on the time of day, with higher rates during peak hours (ex. 4:00pm - 9:00pm).

When your bill is estimated, this means that your gross energy consumption is estimated and so your amount for “What I Would Have Paid without Solar” is calculated using this estimated consumption data. Your bill is always calculated with the most up-to-date rates for your utility based on the season and rate changes.

How is my data estimated?

Ivy estimates gross energy consumption in multiple ways depending on how long you and your community have been billing with Ivy and how long your data has been missing.

The following methods are used in order of priority:

1. Historical consumption: If we have at least one full month of data from the past three months, we’ll use this to estimate your energy usage. We align the days of the week and times of day to match your current billing period for the most accurate profile.

2. Community average: If historical data isn’t available for your unit, we use data from similar units in your community to create an average usage profile. 

  • We identify units with comparable usage patterns using statistical methods, such as normal distribution.
  • For smaller communities (fewer than 30 units), we include 68% of units (1 standard deviation). For larger communities, we include 38% of units (0.5 standard deviations).
  • We calculate an average of these units’ energy consumption every 15 minutes to estimate your usage.

3. Recent usage weekly profile: When some of your data is available historically but not a full consecutive month, we calculate a weekly average based on your available data. This average is then applied to your current billing period to estimate your usage.

How does Ivy correct an estimation?

When your gross energy consumption data becomes available, Ivy calculates a correction called a “True-Up” and applies this to a future bill either as a credit for overestimating or as a debit for underestimating your consumption.

The True-Up amount is calculated by taking your actual consumption data and then recalculating your actual cost of “What I Would Have Paid without Solar”.

We then subtract our estimated cost from the actual cost to calculate the True-Up amount. If the True-Up amount is negative, this indicates that our estimate was larger than the actual cost and you will receive a credit line item on your next bill. 

If the amount is positive, it indicates that our estimate was smaller than the actual cost and you will receive a debit line item on your next bill.

If the True-Up results in a credit that exceeds your current bill, the remaining credit will roll over to future bills. If it’s a charge that significantly increases your bill, Ivy may spread it over multiple billing periods to avoid a sudden large payment.

The True-Up process ensures your bill always reflects your actual energy usage, so you’re never over or undercharged in the long term.

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