Battery Education
From Size to Value: Mastering the Art of Home Batteries
Not all Home Batteries are Created Equal
Size Matters
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Battery size, measured in kilowatt-hours (kWh), is crucial because it determines how much energy your home battery can store and for how long it can power your home during outages or peak times.
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Real-World Application: Choosing the right battery size depends on your household's energy consumption, the energy demands of your appliances, and your backup energy goals (e.g., full vs. partial home power).
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Small Batteries (1-5 kWh): Suitable for smaller homes or those with lower energy needs. These can handle essential loads like lights and small appliances.
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Medium Batteries (6-15 kWh): Ideal for average-sized homes, capable of running the household comfortably but may not cover heavy appliances for more than very short periods.
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Large Batteries (15+ kWh): Best for large homes or high energy usage, capable of running the entire home, including heavy appliances like air conditioners, for several hours.​
Pro's and Con's of Different Backup Power Options
Natural Gas Backup Generator
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Cost: $12,500 installed
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Pro's:
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Always ready when you need it
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Can run the entire home. No need to pick and choose appliances​
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Con's:
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​Sunk cost with no monthly payback
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Higher cost per kWh produced
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Cost per kWh produced: $0.154 cents
Whole Home Batteries tied to Grid
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Cost: $15,000 - $21,000 installed
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Pro's:
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Stable charging from the grid
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Charge when rates are lowest and use when rates are highest
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Savings every month for highest ROI
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Rebates available from Federal Govt
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Con's:
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​Finite power if grid down long-term.
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Cost per kWh produced: $0.05 cents
Batteries tied to Solar System
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Cost: $45,000 - $70,000 installed
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Pro's:
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Can produce and charge when grid down
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Rebates available from Federal Govt.
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Con's:
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​Heavy up-front cost.
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Limited home energy use due to smaller battery and inverter setup
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Ever-changing weather creates unstable solar production
​Cost per kWh produced: $0.12 cents
Importance of Charge and Discharge Rates
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The charge and discharge rates, measured in kilowatts (kW), affect how quickly a battery can be charged or depleted. High rates can handle more instantaneous power needs.
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Charge Rate: Determines how quickly the battery can convert AC power from the grid or DC power from solar panels to stored energy.
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Discharge Rate: Indicates how fast the battery can deliver power to your home.
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Faster rates are crucial during sudden power needs or emergencies.
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They determine the efficiency and performance of your energy management during peak and off-peak times.
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State of Charge (SoC)
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SoC is a percentage that shows how much charge your battery has left compared to its total capacity.
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Importance:
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Essential for managing battery health and understanding when to charge or discharge.​
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Helps prevent overcharging and deep discharging, which can affect battery lifespan.
