Marine Electrical System Planner

The Goal: To determine the right size for your solar array to reduce your reliance on engine or generator charging, saving fuel and noise.

• Complete Step 1 (Energy Audit): A complete audit is essential to know how much power your solar array needs to generate.
• Go to Step 2 (System Sizing): Find the "Recommended Solar Array" box.
• Set Your Goal: Enter the percentage of your daily usage you want to cover with solar (e.g., 75% for good off-grid capability).
• Refine Solar Parameters: To get an accurate recommendation, you must also set the "Cruising Region & Season" and "Avg. Usable Daylight" in Step 3.
• Update: Click the "Update Sizing Recommendations" button in Step 2 to see the result.

The Outcome: The calculator will give you a recommended array size in Watts (W).

The Goal: To determine the minimum daily runtime for a specific generator and charger combination to meet your energy needs. This helps you decide if a particular generator is a good fit for your usage.

• Complete Steps 1 & 2: You need to know your daily demand and your battery bank size first.
• Go to Step 3 (Charging Analysis): In the "AC Generator" section, enter the "Charger Power (AC Watts)" of the generator/charger combination you are considering.
• Determine a Run Time: Adjust the "Run Time (Hrs/Day)" and click "Analyse System & Costs".

The Outcome: Check the "Daily Energy Balance" result. If it shows a deficit, you need a longer runtime or a more powerful generator/charger combination.

The Goal: To choose an inverter powerful enough to run your AC appliances and a charger that can efficiently replenish your battery bank.

• For the Inverter:
  1. In Step 1 (Energy Audit), it is essential to tick the "Peak Load" checkbox for all high-power AC appliances you might use at the same time (e.g., microwave, coffee maker, hairdryer).
  2. In Step 2 (System Sizing), click "Update Sizing Recommendations". The "Recommended Inverter Size" is then calculated automatically.
• For the Charger:
  1. The charger size is directly related to your battery bank size from Step 2.
  2. A common rule of thumb is for your charger's DC output to be between 10-25% of your battery bank's total Amp-hour capacity. For example, a 400Ah lead-acid battery bank would be well-matched with a 40-100 Amp charger.

The Outcome: You will have a recommended minimum *continuous* wattage for your inverter and a target Amp rating for your battery charger.