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Trying to figure out how much battery storage, inverter size, type of charger and what have you to power my houseboat. My plan is to have enough battery storage to run everything using an inverter for AC power using batteries and by charging those batteries daily using a generator for a few hours. The biggest draw would be an occasional few minutes of a microwave to heat food, and also run a tv/monitor along with computer. everything else runs on DC current for short periods of time like fresh water pump. I do have a small a/c air conditioner that pulls maybe 8 amps. Pretty simple setup but also need to know if lead acid batteries are sufficient or do I need special batteris. Any help would be great.
To power a houseboat with battery storage and an inverter for AC appliances using daily generator charging, the most important factors to decide are battery capacity, inverter size, charger type, and whether to use lead-acid or lithium batteries. Lead-acid batteries can work for simple setups, but lithium batteries offer significant efficiency and lifespan advantages for marine use.

Core Components and Sizing
Battery Storage Size
For lead-acid batteries, only about 50% of their stated capacity can actually be used (Depth of Discharge, DoD), so you need double the storage for your daily energy demand.

Example Calculation: If your daily usage is about 3,000Wh (microwave, TV, monitor, computer, small A/C), you’ll need batteries with a minimum rating of around 6,000Wh (or 500Ah at 12V).

For lithium batteries, you can use up to 80-100% of their rated capacity, so you’ll need less overall battery (e.g. 3000-3500Wh for the same usage).

Inverter Size
The microwave is typically the largest load, requiring an inverter rated at 1800-2000W (pure sine wave type).

TV, monitor, and computer can be run off smaller inverters, but if combined with the microwave, the total inverter size should meet or exceed the microwave’s surge requirement. For a standard 1000W microwave, a 2000W pure sine wave inverter is usually necessary for safety.

A/C units that pull 8 amps at 120VAC = 960W; check their startup surge rating before sizing inverter.

Charger Type (for Generator Charging)
Use a smart charger or inverter/charger sized for the capacity of your battery bank. Match the maximum charging rate allowed by the batteries so you can charge efficiently in a few hours.

Lead-acid batteries accept lower charge rates; lithium batteries can accept higher currents and charge faster.

Lead-Acid vs. Lithium Batteries
Feature Lead Acid Lithium (LiFePO4)
Cycle Life 300-500 cycles 3,000–15,000 cycles
Usable Capacity (%) 50% 80–100%
Weight (100Ah) ~30 kg 10–13 kg
Maintenance High Low
Charging Speed Slow Fast
Cost Low Initial Higher Initial
Lead-acid is budget-friendly for basic setups with low cycle demands. Lithium (LiFePO4) batteries are recommended for longer lifespan, lighter weight, deeper discharge, and faster charging, especially for frequent use or higher daily energy loads.

Quick Recommendations
Battery Bank: 500Ah (12V) for lead-acid, 250–300Ah (12V) for lithium, based on 3–3.5kWh day usage.

Inverter: 2000W pure sine wave inverter, minimum, capable of surge demands of microwave and A/C.

Charger: Match battery bank and generator output. Smart charger with proper amps for lithium or lead-acid type.

Microwave Use: For brief microwave use (1000W) and AC appliances, the inverter and battery bank as above are sufficient.

Practical Notes
Always size your system for worst-case peak power (e.g. A/C + microwave running briefly together).

Use fused wiring and marine-grade cables for safety.

Lithium batteries require compatible chargers/inverter settings and are initially more expensive but offer clear benefits long-term.

For occasional generator charging (daily or every few days), size for full recharge in 3–4 hours.

Lithium batteries (LiFePO4) are strongly recommended for a houseboat setup where weight, longevity, and recharge speed are important, but lead-acid can work for basic or budget builds.

A setup with a 2000W pure sine wave inverter and 250Ah lithium battery bank (or 500Ah lead-acid) will cover your described loads, allowing daily generator charging for AC power on your houseboat.