The best home battery systems for solar PV have the edge for several reasons. These include response speed and intelligent charging, which we’ve examined in previous blog entries – and conversion rates, which we look at today.
Solar photovoltaic modules produce ‘direct current’ (DC) electricity, and batteries store it in DC as well. Households, however, use alternating current (AC). Discovering the reasons for this difference takes us back over 100 years – and it’s worth a read if and when you have time, but both current types have their uses, which is why each type is so widely used today!
Efficient conversion = more power
What’s important to note, however, is that for safe, effective performance, DC power must be converted to AC, a process carried out by an ‘inverter’. With conventional AC-side batteries, three conversions are required.
SOLARWATT’s multi-award-wining MyReserve is unlike other batteries as it’s installed on the DC side, storing direct current from the PV system, so only one conversion stage is required. Only when the electricity is consumed in the household is it changed to alternating current.
This makes a big difference in performance, for while ordinary batteries leave households with a conversion rate of only 75%, MyReserve produces 90% of the power generated by modules. That’s a substantial difference in performance and ultimately, cost.
So for efficiency and economy, you’re better of with MyReserve, by SOLARWATT.
Photovoltaic modules produce direct current (DC) and batteries store electricity in DC as well. Households, however, use alternating current (AC). The DC Power must be converted to AC power and this conversion is performed by the inverter.
Standard AC battery:
Electricity from the roof goes through an inverter and is converted into alternating current. If it is sent to a conventional battery, it is converted back into direct current. Then as the battery discharges the current must be converted once again to alternating current. With each conversation you loose some of your precious solar power and end up with only 75 % for your own use.
Our battery is installed before the inverter. It stores the direct current from the PV system . Only when the electricity is consumed in the household, it is converted into alternating current. This leaves over 90 % of your own solar power available – that pays off.