Path-Q Solar
How should battery value be assessed when it provides both bill savings and backup power?
Answer
Assess the battery as two related services: measurable operating savings and the value of improved outage resilience. Do not judge it only by bill savings; compare the incremental cost with both the expected economic benefit and the importance of keeping selected loads operating.
Key points
- Bill savings depend on tariff structure, solar production, load timing, battery efficiency, and control rules.
- Backup value depends on the protected loads, outage likelihood and duration, and the consequences of interruption.
- Separate the value of routine cycling from the value of stored energy reserved for outages.
- Include replacement, degradation, maintenance, financing, and installation costs in the comparison.
What it depends on
- Electricity rates and billing structure
- Battery usable capacity, power rating, efficiency, and warranty limits
- Outage history and the financial or personal consequence of interruption
- Whether a generator or other backup option is available
Risks and trade-offs
- Projected savings may be overstated if actual load timing differs from assumptions.
- Assigning a precise monetary value to avoided inconvenience or business interruption is uncertain.
- A battery can provide backup power but still fail to support every load simultaneously.
Information you may need
- Recent interval or time-of-use electricity usage if available
- System price and financing terms
- Critical loads and the required outage duration
- Expected battery degradation and warranty conditions
Your next step
What to do next
Compare the battery with no battery and with alternative backup options using separate calculations for annual bill savings, ownership cost, and the value of protected outage service.
Path-Q
Find the right next step
Answer a few questions and we’ll narrow your options.
Loading…
SQ01979