Home Backup Battery Systems

You can store the energy produced by your solar panels or from your utility grid for use at a later time using storage batteries. The majority of storage battery solutions also contain elements for intelligent energy management together with solar generation and energy consumption monitoring.

These characteristics limit the amount of energy that is drawn from the grid, which lowers costs and accelerates payback.

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BENEFITS
  - To save money, use grid electricity or solar energy at the times that are best for your utility rate plan, especially if you are on the Time-of-Use rate plan.
  - Use nighttime solar energy produced during the day. For instance, you may use the energy produced by your solar panel system during the day to charge your electric vehicle at night.
  - The majority of utility companies offer no credit or very little credit for solar energy generated beyond what you consume and exported to the grid. This extra energy can be saved in storage batteries and used later, effectively being credited at the utility's retail rate.
  - Use in crisis situations like blackouts or power outages.
  - Off-Grid Living You might be totally independent of the grid, depending on how much energy you need.

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DECISION FACTORS
The major factors include:

  - Your Goals
  - Usage pattern
  - Storage System capacity
  - Cost (now and in the future)
  - Available incentives
  - Electricity costs (now and in the future)
  - Solar System size
  - Warranty
  - Payback period

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1. Warranty

A home battery typically charges and discharges once every day (one cycle). These cycles cause the battery, like any battery, to age over time and lose some of its ability to store energy. The battery must satisfy a predetermined standard for the duration of the warranty.

   Tesla under typical usage conditions, guarantees that the Powerwall will hold a 70 percent capacity for 10 years or 3200 cycles.

   Enphase is guaranteed with a 70 percent capacity over 10 years or 4,000 cycle warranty regardless of usage.

   FranklinWH is guaranteed with a 70 percent capacity over 12 years or 6000 cycles. 

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2. Size (Capacity and Power)

The amount of energy that may be stored and used at any given time ultimately depends on the size of the battery. A battery's power and useful capacity determine its size.
The overall capacity of the battery, which is expressed in kilowatt-hours (kWh), represents the battery's maximum storage capability. Usable capacity, which denotes the maximum energy present in a fully charged battery, is what we are generally concerned in.

   Tesla clocks in with an impressive usable capacity of 13.5 kWh capacity, and 5.0 kW of power. The Powerwall can put out a peak power of 7.0 kW but only for 10 seconds at a time.

   Enphase IQ 10 falls slightly short of the Powerwall in power and capacity, with a usable capacity of 10.8 kWh capacity, and 3.84 kW of power. The Enphase IQ 10 can put out a peak power of 5.7 kW but only for 10 seconds at a time. The smaller Enphase IQ 3 follows up with a usable capacity of 3.36 kWh capacity, and 1.28 kW of power. The Enphase IQ 3 can put out a peak power of 1.92 kW but only for 10 seconds at a time.

   FranklinWH  holds 13.6 kWh capacity. The unit can output 5,000 watts of continuous power and surge to 10,000 watts for 10 seconds. 

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3. Efficiency

A measurement called the Depth of Discharge (DoD) evaluates how much energy a battery drains overall in relation to its whole capacity. A battery with a high DoD is one that is both extremely effective and of the highest caliber.

The efficiency of a battery is reflected by 3 factors:

 - Its depth of discharge
- Its round trip efficiency
- Battery degradation over time

   Tesla certainly meets the criteria for efficiency with a DoD of 100 percent.. Combined with a round trip efficiency of 90 percent (10 percent energy lost), the Powerwall is one of the most efficient batteries on the market. Finally, an expected degradation of 3 percent reflects the high quality of the product.

   Enphase (both sizes) also boasts a DoD of 100 percent; however, the round trip efficiency comes in 89 percent. As with the Powerwall, a degradation of 3 percent indicates a high-quality product.

   FranklinWH battery has a roundtrip efficiency of 85 percent. 

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4. Chemistry

• Both the Powerwall and the Enphase IQ are considered safe and have extensive safety ratings.

• The Enphase IQ LFP variation is the safer option as it inherently produces less heat.

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5. Thermal Cooling

• Like other batteries, the Powerwall has an optimal operating temperature range from 32℉ to 86℉ (0℃ to 30℃). However, the liquid cooling system allows the Powerwall to operate in temperatures from -4℉ to 122℉ (-20℃ to 50℃).

• At low temperatures, the Powerwall can preheat cells in what is called preconditioning, enabling them to function.

• Like the Powerwall, the Enphase IQ operates best from 32℉ to 86℉ (0℃ to 30℃) but is still able to operate with ambient temperatures reaching from 5℉ to 131℉ (-15℃ to 55℃).

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6. Inverter

• The Powerwall, like many home batteries, functions with a single large inverter. This inverter may be sourced from several companies.

• Departing from the standard single inverter design, the Enphase IQ is designed with a unique array of 12 micro-inverters that work together.

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Investing in one of the aforementioned items is worthwhile if you wish to stick with a reputable brand. It does not seem like a bad idea to upgrade to a newer product with excellent specifications if you want to. You can't go wrong with either of these 3 home batteries. It all depends on your size, power, and budget requirements.