Get matched with top energy efficiency auditors in Bruce, WI

To determine the right size generator for your house, you should calculate the total wattage of the appliances and devices you want to power during an outage. List all essential items, note their start-up wattages, and add them together.

Here are some typical wattage requirements for common appliances:

• Refrigerator: 600 watts

• Large dehumidifier: 700 watts

• Large window air conditioner: 1,400 watts

• Water heater: 3,000 to 4,500 watts

• Electric furnace: 5,000 to 25,000 watts

A 7,500-watt generator might be sufficient for essentials like a refrigerator, freezer, well pump, and lighting circuits. However, for high-demand items like a water heater or furnace, a whole-home generator is a better choice. A portable generator may be enough if you only need to power a few critical items.

While home square footage can offer a rough estimate, it is not always a reliable indicator. For reference, here are some typical generator sizes based on square footage:

• 1,000 sq ft: 6–9 kW

• 1,500 sq ft: 7–10 kW

• 2,000 sq ft: 10–14 kW

• 2,500 sq ft: 12–16 kW

• 3,000 sq ft: 16–20 kW+

For the most accurate sizing, consult a professional who can calculate your home's peak and average power consumption and recommend the optimal generator.

A home energy audit costs about $420 on average, with prices ranging from $100 to $2,250 or more. The final cost depends on factors like your home's size, location, the thoroughness of the audit, and the specific tests performed. A basic Level 1 walk-through inspection typically costs between $150 and $200, while a comprehensive Level 3 audit with detailed testing and a report costs around $900. Homeowners may be able to use the 2022 Inflation Reduction Act’s Energy Efficient Home Improvement credit to cover up to $150 of the audit cost.

Costs for common individual tests include:

• Blower door test: $350

• Duct testing: $100

• HERS test: $375

• HERS certification: $200

• Infrared imaging: $200

While many states require all new construction to undergo blower door tests, it’s not a requirement for existing homes. But in both cases, a blower test helps confirm that the contractor has sealed the exterior, that the type of ductwork installed is functioning properly, and that your home is as efficient as possible.

Window AC units use a fair amount of electricity, but significantly less than central AC systems. Because they are more energy-efficient for cooling individual rooms or small spaces, their usage is comparatively low. On average, a window AC unit consumes between 500 and 1,400 watts, while a central AC system uses over 3,500 watts—meaning a window unit uses about one-third of the energy. This typically translates to a monthly running cost of $15 to $40, although this can vary depending on external factors.