As part of the Enphase IQ family of products, the company has released its Enphase IQ Battery 5P. This battery offers some improvements for select clients in Southwest Florida, all at a similar price to the existing 3T and 10T batteries (for equal storage capacity).
The Enphase 5P battery has just half of the battery capacity of the existing 10 and 10T batteries, which are based on the same chemistry. The defining factor for the 5P is that it has more instantaneous output power to start up and run large loads continuously. But this is at the cost of capacity, or time you can run those large devices.
As we have pointed out before, the Enphase battery (and many others) are not just batteries in the traditional sense. They include a battery management system and multimode inverters that can charge the batteries from AC power (grid and solar) and discharge AC power to loads in your house or the grid (which you would not want to do in Florida because we have Netmetering). So you can’t compare capacity alone when considering “battery” options. It’s not that simple. These are relatively new “appliances” that are technically Energy Storage Systems (ESS) as defined by the National Electrical Code.
To understand the reason Enphase released a battery with lower capacity* than existing options, you have to look at the use cases. One of the downsides of the Encharge 10/10T batteries is they don’t have enough inverter output rating to start up large loads like air conditioning. By increasing the power of the microinverters in the 5P relative to the battery capacity, you get a smaller battery that can very quickly deliver power and recharge.
* The Encharge 10 battery is actually made up of three 3.36kWh batteries that can function individually, but that’s not point here. The question is why Enphase released a battery with lower capacity but higher output than their flagship 10 and 10T batteries.
The use case for this high output / low capacity battery is for situations where you do want to start and run heavy loads, but that comes by sacrificing the length of time you can run them. This works great in cooler climates where you still might need air conditioning, but not for the long hours that we need in Southwest Florida when backup power is critical. So while two 5P batteries might start your air conditioner, you won’t be able to run it for very long. It certainly would not get you through the night. With the Encharge 10 batteries, we recommended 3 batteries minimum typically for central air conditioning. The reason for this is you usually need three of these to just start up an air conditioner reliably, and the large capacity is needed to run the air conditioning for long spans.
Recently a client approached us asking if they could put in a small battery to run the air conditioner during the day only when solar power was plentiful, but only run lights and small loads at night. This is a perfect use case for the new 5P battery (realistically two or three of them, however). That will cost a lot less than three 10kWh batteries, but they will be sacrificing air conditioning and any other large loads at night.
There are some other advantages to the 5P battery. Previously we were faced with a limit of 40kWh of total storage capacity with Enphase’s IQ battery system. That is now increased to 80kWh for large homes with extreme demands. The 5P, along with the new System Controller 3 and IQ Combiner 5 are now hard-wired for communications, which should fix some of the wireless communication headaches that some Encharge 10 customers have experienced. There are also some PV sizing advantages for people who want big PV systems with small batteries, and it provides better design flexibility since fewer batteries can be used in a whole home scenario without carving out a critical load panel. In addition, some installer-friendly changes were made, particularly with conduit routing (which will make systems look better as well) and field replaceable parts that could same complete battery replacements in some cases of warranty repair.
They also increased the warranty from 10 years to 15 years, adding some value to a product that will surely be more expensive per unit of capacity and will likely be among the premium options on the market.
Enphase will continue manufacturing the IQ 10 series. First, the 5P and 10T are not compatible due to needing a different system controller and communications protocol. Second, there are cases where the 10T might be better for physical space considerations. But we expect most clients to go with the higher-powered, lower-capacity 5P battery, given the pricing we are seeing come from Enphase.
Existing microinverter system owners can use the 5P battery as long as they do not currently have a System Controller 2 and as long as they purchase a communication upgrade module to allow the existing Gateway device to work with the new wired protocol.
As always, Florida Solar Design Group is at the forefront of Enphase design and installation knowledge and is now offering the 5P battery for new contracts.