Backup Generator (Generac 12kw) vs. Backup Battery (PowerWall 13.5kw) : Which Is Better?
Introduction
When it comes to ensuring your home remains powered during an outage, you have two main options: a whole home backup generator or a whole home backup battery. Both have their advantages and disadvantages, and the right choice depends on various factors including price, return on investment (ROI), installation, warranty, and additional benefits like using the battery during time-of-use (TOU) rates to save on electricity costs.
This article will explore these factors in depth to help you make an informed decision using real data from the Generac 12kW generator and the Tesla Powerwall 2 13.5kW battery.
Price
Generac 12kW Generator:
Initial Cost: The Generac 12kW generator typically costs between $4,500 and $6,000.
Installation Costs: Professional installation, including connection to the home’s electrical system, typically adds another $5,000. This brings the total cost to $9,500 to $11,000.
Fuel Costs: Generators run on fuel such as natural gas, propane, or diesel. The fuel cost depends on usage and local prices. On average, running a generator on natural gas can cost around $0.14 per kWh. For a 12kW generator running at full capacity for 24 hours, this could be around $40.32 per day.
Maintenance Costs: Regular maintenance, including oil changes, filter replacements, and inspections, can cost between $200 and $500 annually. Generac recommends maintenance every 200 hours of operation or once per year.
Tesla Powerwall 2 (13.5kWh):
Initial Cost: The Tesla Powerwall 2 costs approximately $7,500. Additional hardware like the Tesla Gateway can add $1,000 to $2,000, bringing the total hardware cost to around $8,500 to $9,500.
Installation Costs: Installation costs can range from $2,000 to $4,000, depending on the complexity of the setup and local labor rates. This brings the total installed cost to approximately $12,500 to $15,500.
Operational Costs: Battery systems typically have lower operational costs as they don’t require fuel. The main cost is the electricity used to charge the battery from the grid, which depends on local electricity rates. For example, if off-peak electricity costs $0.10 per kWh, charging the Powerwall fully (13.5 kWh) would cost $1.35.
Return on Investment (ROI)
Generac 12kW Generator:
Initial and Installation Cost: $9,500 to $11,000.
Fuel Costs: At $0.14 per kWh, the cost to run the generator at full capacity for 24 hours is approximately $40.32. Assuming 10 days of use per year, this amounts to $403.20 annually.
Maintenance Costs: Regular maintenance costs between $200 and $500 annually.
Total Annual Costs: Fuel and maintenance together total approximately $603.20 to $903.20 per year.
ROI Calculation: The ROI for a generator largely depends on the frequency and duration of power outages. In areas with frequent outages, the investment may be justified sooner due to the necessity of constant power supply. However, for less frequent outages, the payback period can extend significantly, often beyond 10 years when considering the annual operational and maintenance costs.
Tesla Powerwall 2 (13.5kWh):
Initial and Installation Cost: $12,500 to $15,500.
Operational Costs: Assuming off-peak electricity rates of $0.10 per kWh, charging the Powerwall fully costs $1.35. If the battery is cycled daily, the annual cost for electricity is approximately $492.75.
Additional Savings with TOU Rates: By using the Powerwall to avoid peak electricity rates (e.g., $0.30 per kWh), substantial savings can be realized. For example, if peak usage of 13.5 kWh is shifted daily, the savings can be around $985.50 annually.
Total Annual Savings: Considering operational costs and savings, the net annual savings can be approximately $492.75.
ROI Calculation: The ROI for the Powerwall can be faster due to the additional savings from TOU rates. In areas with TOU pricing, the payback period can be significantly shorter, potentially within 8 to 10 years.
Installation
Generac 12kW Generator:
Installation Process: Installing a Generac 12kW generator involves several steps, including selecting a suitable location, preparing a concrete pad or other foundation, connecting the generator to your home's electrical system, and setting up the fuel supply (natural gas, propane, or diesel). The process typically requires a professional electrician and possibly a plumber for the fuel connection.
Time Required: Installation usually takes 1 to 2 days, depending on the complexity of the setup and any additional electrical or plumbing work required.
Installation Cost: The installation cost for a Generac 12kW generator is typically around $1,000. This cost covers the labor and materials needed to connect the generator to your home's electrical system and set up the fuel supply.
Tesla Powerwall 2 (13.5kWh):
Installation Process: Installing a Tesla Powerwall 2 involves mounting the battery on a wall (indoors or outdoors), connecting it to your home's electrical panel, and integrating it with the Tesla Gateway for monitoring and control. This installation also requires a professional electrician.
Time Required: Installation typically takes 1 to 2 days, depending on the complexity of the electrical setup and any additional work needed to accommodate the battery.
Installation Cost: The installation cost for a Tesla Powerwall 2 ranges from $2,000 to $4,000. This cost includes labor and materials for mounting the battery, connecting it to the electrical system, and integrating the necessary monitoring equipment.
Warranty
Generac 12kW Generator:
Standard Warranty: Generac offers a standard 2 to 5-year limited warranty on their generators, which covers parts and labor for repairs due to defects in materials or workmanship.
Extended Warranty Options: Generac provides extended warranty options that can extend coverage up to 10 years for an additional cost. This extended warranty can cover more extensive repairs and replacements, giving homeowners peace of mind for a longer period.
Coverage: The warranty typically includes the generator engine, alternator, and other critical components but may exclude wear-and-tear items such as filters and spark plugs.
Tesla Powerwall 2 (13.5kWh):
Standard Warranty: The Tesla Powerwall 2 comes with a 10-year limited warranty. This warranty guarantees that the Powerwall will maintain at least 70% of its capacity after 10 years of usage.
Performance Guarantee: Tesla's warranty also includes a performance guarantee, ensuring the battery's capacity does not degrade below a certain level within the warranty period.
Coverage: The warranty covers defects in materials and workmanship, as well as significant capacity loss, ensuring reliable performance throughout the warranty period.
Additional Benefits: Time-of-Use Rates
Tesla Powerwall 2 (13.5kWh):
One of the significant advantages of the Tesla Powerwall 2 over traditional generators is its ability to leverage time-of-use (TOU) rates to save on electricity costs. Here’s how it works:
Charging During Off-Peak Hours: The Powerwall can be programmed to charge during off-peak hours when electricity rates are lower. For example, if off-peak electricity costs $0.10 per kWh, charging the Powerwall fully (13.5 kWh) costs $1.35.
Discharging During Peak Hours: The stored energy can be used during peak hours when electricity rates are higher, such as $0.30 per kWh. By discharging 13.5 kWh during these times, the homeowner can save $4.05 (13.5 kWh x $0.30) per day.
Annual Savings Calculation: If this cycle is repeated daily, the annual savings can be substantial. For example, saving $4.05 per day amounts to approximately $1,478.25 per year ($4.05 x 365 days).
Generac 12kW Generator:
Fuel Cost and TOU Rates: Generators do not benefit from TOU rates since they rely on fuel rather than electricity from the grid. Their operational costs remain constant regardless of the time of day.
Usage During Outages Only: Generators are typically used only during power outages and do not provide any cost-saving benefits during normal grid operation. Whole-Home Generator vs Whole-Home Backup Battery
Summary of Benefits:
Tesla Powerwall 2: By using TOU rates, the Powerwall not only provides backup power during outages but also helps reduce electricity bills by shifting energy usage to off-peak times. This dual benefit significantly enhances the ROI and overall value of the battery system.
Generac 12kW Generator: While effective during outages, the generator does not offer any financial savings during normal operations, making it solely an emergency backup solution.
Conclusion - Whole-Home Generator vs Whole-Home Backup Battery
When deciding between a whole home backup generator and a whole home backup battery, it’s essential to consider various factors, including price, return on investment (ROI), installation, warranty, and additional benefits like time-of-use (TOU) rates. Here’s a summary based on the Generac 12kW generator and the Tesla Powerwall 2 (13.5kWh):
Price:
Generac 12kW Generator: Initial and installation costs range from $9,500 to $11,000. Ongoing fuel costs at $0.14 per kWh and annual maintenance add $603.20 to $903.20 per year.
Tesla Powerwall 2: Initial and installation costs range from $12,500 to $15,500. Operational costs are minimal, with approximately $1.35 per full charge cycle.
Return on Investment (ROI):
Generac 12kW Generator: ROI depends on the frequency and duration of power outages. Higher annual operational and maintenance costs can extend the payback period beyond 10 years.
Tesla Powerwall 2: With TOU rates, the Powerwall can significantly reduce electricity bills, providing annual savings of around $1,478.25. This leads to a potentially faster ROI, often within 8 to 10 years.
Installation:
Generac 12kW Generator: Installation is complex, requiring professional electrical and possibly plumbing work, taking 1 to 2 days and costing around $1,000.
Tesla Powerwall 2: Installation is also professional but typically simpler, taking 1 to 2 days and costing $2,000 to $4,000.
Warranty:
Generac 12kW Generator: Standard warranty of 2 to 5 years, with extended options up to 10 years. Coverage includes major components but excludes wear-and-tear items.
Tesla Powerwall 2: A comprehensive 10-year warranty with a performance guarantee, ensuring the battery retains at least 70% of its capacity.
Additional Benefits:
Generac 12kW Generator: Provides reliable power during outages but offers no cost-saving benefits during normal grid operation.
Tesla Powerwall 2: Can leverage TOU rates to save on electricity costs, providing both backup power and significant annual savings.
Final Verdict:
Generac 12kW Generator: Best suited for areas with frequent and prolonged power outages where immediate and reliable backup power is essential.
Tesla Powerwall 2: Ideal for homeowners looking to save on electricity bills through TOU rates while also needing reliable backup power during outages. The potential for faster ROI and significant annual savings make it a compelling choice for many households.
By evaluating these factors, you can make an informed decision on which backup power solution best meets your needs and budget. Whether you prioritize immediate backup power or long-term savings and efficiency, understanding the strengths and limitations of each option will help you choose the right system for your home.
Commentaires