How can I improve savings on my project?

If the savings on a project are coming out lower than expected — or your customer's post-solar utility bill is higher than it should be — there are two categories of settings to check. Some live in Aurora's financial model; others live at the design and utility level. Start with the category that matches your symptom.

In this article:

• Financial modeling settings to check
• Design and utility settings to check
• Understanding residual post-solar utility bills
• Understanding the difference between % energy offset and % bill savings
• FAQ

Financial modeling settings to check

These settings affect how Aurora calculates the financial value of the system — lifetime savings, NPV, LCOE, and payback period. If the numbers look off but the design looks right, start here.

Discount rate

For cash purchases, the discount rate is the single biggest lever on Lifetime Savings and NPV. The higher the discount rate, the lower the present value of future savings — which directly reduces the figures shown in Sales Mode.

If Lifetime Savings or NPV looks unexpectedly low on a cash project, try reducing the discount rate. A rate between 4–8% is typical for consumer solar. To update:

1. Navigate to the Financing page (the Bank icon in the top nav).
2. Click the gear icon in the upper right to open Advanced financing settings.
3. Click Edit and update the Cash flow discount rate field.
4. Click Save.

Per-project discount rate changes only affect that design. To change the default for all future projects, an admin must update the rate in Settings > Financing > Pricing & financing. Changes to the account default do not apply retroactively to existing projects.

See the Discount rate article for a full explanation of how to choose the right value.

Utility escalation rate

The utility escalation rate controls how fast the customer's electricity costs are projected to grow over the system life. If escalation is set to 0% or very low, projected savings over 25 years will appear modest even for a well-designed system.

The utility escalation rate is set at the account level — it is not a per-project field in the Advanced financing settings panel. To check what rate is in effect:

1. Go to Settings > Utility and tax rates.
2. Check the Default rate in the Residential or Commercial tab for the relevant location.

To update the account-wide default, an admin must edit the rate in Settings > Utility and tax rates. See Utility and Tax Rates: Account Configuration for instructions.

Changes to the utility escalation rate only apply to new projects. To apply an updated rate to an existing project, duplicate it.

Other Advanced financing settings

Several other settings in the Advanced financing settings panel affect savings calculations:

To access these settings, navigate to the Financing page (the Bank icon in the top nav) and click the gear icon in the upper right. Click Edit to make changes. See Advanced financing settings for a full field reference.

Applied incentives

Incentives that are missing, misapplied, or outdated can make savings appear lower than they should — or produce unrealistically optimistic figures.

Things to check on the Pricing > Incentives page:

• Are all applicable state and local incentives applied? SRECs, utility rebates, and programs like SGIP or MA SMART can significantly affect the financial picture.
• Is a federal ITC still applied from a pre-2026 project template? The residential ITC (Section 25D) expired December 31, 2025 for customer-owned systems. Remove it from residential cash/loan projects if it is still showing.
• Are incentive disbursement types set correctly? A lump-sum SREC paid in Year 1 has a different effect on Net Cost than an annual SREC paid over 15 years.

Design and utility settings to check

These settings affect how much electricity the system produces and how Aurora models the customer's utility bill. If the post-solar bill looks too high, or if system production seems low, check these first.

Utility rate

Savings calculations are only as accurate as the utility rate selected. If the wrong rate is applied — especially one with lower energy charges or a less favorable net metering structure — savings will appear lower than they should be.

1. From the Project Overview page, click the Utility rate field and verify it matches the customer's actual utility and rate plan.
2. In Sales Mode, confirm the post-solar utility rate is correctly set if the customer will switch rate plans after going solar.

In Design Mode, the post-solar utility rate field does not auto-populate from the project-level setting. If a post-solar rate is needed, it must be entered directly at the design level.

Utility Bill Savings settings

Several settings within the utility billing model have a large effect on projected savings. To access them:

1. Open the design in Design Mode.
2. Click the Size / Production / Savings area in the top right of the design canvas.
3. Click Bill Savings.

Key settings to review:

• Export rate — The dollar value per kWh Aurora credits for excess solar generation sent back to the grid. A low export rate reduces the value of solar production that exceeds the customer's consumption. If the customer is on a rate with a low net surplus compensation (NSC) rate — such as California NEM 3.0 — savings will naturally be lower than on full retail-rate net metering. Make sure the export rate reflects the customer's actual utility compensation policy.
• True-up period — When net metering credits expire and are settled. A December true-up means unused credits expire at year-end and are not applied to January bills — which can create a large residual bill in January and February. Changing the true-up period to match the customer's actual utility rule will correct the bill pattern.
• Bill frequency — For the rare case where bills are annual rather than monthly, Aurora models the financial exposure differently. Confirm this matches the utility's actual billing cycle.

Irradiance and panel placement

Production drives savings. If panels are shaded, poorly oriented, or too close together, production — and therefore savings — will be reduced.

1. Open the design in Design Mode.
2. Run irradiance analysis (click the Irradiance button in the toolbar).
3. Look for panels with low solar access or TSRF values. Consider repositioning or removing panels in heavily shaded areas.

Understanding residual post-solar utility bills

Even with a system sized to offset 100% of a customer's energy consumption, they will almost always have some residual utility bill. This is normal and expected. Common causes:

• Fixed monthly utility charges — most utilities charge a fixed customer fee regardless of consumption, which solar cannot eliminate.
• True-up timing — credits from months with excess solar generation may not fully offset months with high consumption, depending on when the true-up period occurs.
• Time-of-use rate mismatch — if the customer's rate charges more in the evening (when solar is not producing) than during the day (when solar is producing), the net exchange may not fully cover costs.
• Incomplete energy offset — if the system is sized below 100%, a portion of the customer's consumption is always purchased from the grid.

To troubleshoot a post-solar bill that's higher than expected, go to Design Mode > Utility Bill Savings and review the monthly bill comparison chart. The chart shows each month's pre-solar and post-solar bill, making it easier to identify which months are driving residual charges and why.

Understanding the difference between % energy offset and % bill savings

These two metrics look similar but measure different things:

FAQ

My savings changed after I duplicated a project. Why?

When you duplicate a project, it copies the account default settings at the time of duplication — not the settings from the original project. If the account defaults have been updated since the original project was created, the duplicate will reflect those new defaults. Check the discount rate, escalation rate, and financing settings to confirm they match your intent.

Why do Lifetime Savings and Utility Bill Savings show different numbers?

Utility bill savings is the gross reduction in electricity bills — it does not subtract the cost of the solar system. Lifetime savings is the net financial gain: utility bill savings minus the system investment, financing costs, and O&M. Lifetime savings is almost always lower than total utility bill savings. Both figures are correct; they measure different things.

The customer's bill went up in December. Is there a bug?

Not necessarily. If the true-up period is set to December, Aurora models solar credits expiring at year-end and the full December bill posting before any January credits accumulate. This is accurate modeling of how annual net metering true-up works. Check the true-up period in the Utility Bill Savings panel and confirm it matches the customer's actual utility rule.

Related articles

• Financial analysis: Overview
• Discount rate
• Utility and Tax Rates: Account Configuration
• Advanced financing settings
• Working with Utility Rates in Aurora
• Modeling California's NEM 3.0 in Aurora
• Incentives