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Heat Load Analysis - Heating Degree Days
If you have a heat-load analysis performed on your property, the results are likely to come back in a very odd measurement: Btu per heating degree day per square foot. How can you use this to work out your solar thermal space heating requirements?
Options for Backup Generators
A genset unit is durable and long-lasting if it is maintained well. A good quality generator has no problem with run times but it should be maintained regularly. For example, a diesel engine may need servicing at various hour intervals, such as 25, 250, 500 and 1,000 hours of operation.
How do Batteries Work?
Why is a battery bank necessary? Because an off-grid system does not allow you to store electricity easily and economically. There are other ways to store electricity but they are more expensive.
How to Size PV Battery Backups
The more energy you consume, the bigger the storage facility you need. Buckets are measured in liters or gallons; battery capacity is measured in watt- or amp-hours. If the battery uses a higher voltage source for charging (like a full-strength PV array), you will enjoy a higher voltage recharge – a battery bank of 24V can record a 30V voltage when it goes through equalization charging.
What are Diversion Loads?
An electrical load is normally required all the time to work a wind or hydro turbine. The energy generated from these sources needs to be redirected elsewhere when the batteries are fully charged. This is where the diversion load steps in.
Equalizing Battery Charging
CAUTION!
Sealed or "maintenance-free" batteries need no equalization charging.
Equalizing these batteries can cause fire or explosion.
The equalization process can be visualized as batteries being buckets with electricity being the water filling the buckets. One bucket is one battery cell.