Portable Power Stations

Reed_Richards

QrizB said:

JKenH said:

That’s the theory, anyway, but I have not dared to try it yet. I am wondering if anyone with batteries and an emergency back up outlet has actually tried plugging the house in. 

I think @Reed_Richards has, although his system is set to switch automatically?
You've also gained a mention over on the main "Energy" board:
https://forums.moneysavingexpert.com/discussion/comment/79249828/#Comment_79249828

I do have automatic switchover but only for my lighting and one electrical circuit that covers my fridge, freezer and router.  When I used to have an oil boiler that was also on a backup-circuit.

The solar panels continue to function so long as my inverter has power so I must be careful not to run the battery "dry" in the event of a prolonged power outage.  During the aftermath of Storm Arwen I switched my fridge and freezer off overnight to ensure the battery was not exhausted before I could charge it the following day.

My electrician, unbidden by me, gave the house an independent earth. 

amosmosley

Reed_Richards said:

QrizB said:

JKenH said:

That’s the theory, anyway, but I have not dared to try it yet. I am wondering if anyone with batteries and an emergency back up outlet has actually tried plugging the house in. 

I think @Reed_Richards has, although his system is set to switch automatically?
You've also gained a mention over on the main "Energy" board:
https://forums.moneysavingexpert.com/discussion/comment/79249828/#Comment_79249828

I do have automatic switchover but only for my lighting and one electrical circuit that covers my fridge, freezer and router.  When I used to have an oil boiler that was also on a backup-circuit.

The solar panels continue to function so long as my inverter has power so I must be careful not to run the battery "dry" in the event of a prolonged power outage.  During the aftermath of Storm Arwen I switched my fridge and freezer off overnight to ensure the battery was not exhausted before I could charge it the following day.

My electrician, unbidden by me, gave the house an independent earth. 

That's good to know that you have an automatic switchover for your lighting and some electrical circuits, and that your solar panels continue to function as long as your inverter has power. It's also a smart move to turn off your fridge and freezer during a prolonged power outage to conserve the battery. Having an independent earth is also a great precautionary measure to ensure safety and reliability of your electrical system. Just make sure to check the functionality of your automatic switchover and earth regularly and have them inspected by a licensed electrician if necessary.

2nd_time_buyer

JKenH said:

I have made reference to my portable power station in other posts but as I believe these are very useful bits of kit for some people I thought a separate thread might be a good idea. 

In case any has not come across them a PPS consists of a an MPPT charge controller, a lithium battery and an inverter. Their primary use is for outdoor camping coupled with a portable solar panel but they have other uses,for instance providing power occasionally in an outbuilding such as a garage, summerhouse or home office where there is no mains supply. In the US it seems quite a few people use them for their off grid cabins. There are a wide range of battery sizes (from a couple of hundred Wh to over 3kWh and inverter outputs up to around 3kw. My PPS has a nominal capacity of 2.4kWh (just under 2kWh useable) and an output of 1kW (1.2kW) peak.

The first point I would like to make is that for most people a grid tied battery is a better option and the bigger the battery capacity you are after the better that option becomes. With some PPSs there is the option to add additional battery capacity but most smaller capacity ones are stand alone units so are not expandable. For some of us though a grid tied battery is not an option so a PPS gives us a cheap alternative to a professionally fully installed battery, albeit with much reduced functionality.

Some of the drawbacks:

Limited battery capacity unless you buy a more sophisticated model with expandable battery options and then it gets expensive. 

Limited charging rate - mine only charges at 210w from the grid or up to 500w from a solar panel so even on my GoFaster tariff I can only add 1kWh at cheap rate. It is though, a low enough charge rate to leave it on topping up during daylight hours.
Limited AC output potential. 

They cannot (generally) be connected to the house supply to cover overnight loads or supplement the grid supply when solar is low nor can they follow grid usage and only charge when there is spare PV.
There is some fan noise but you can put the PPS in another room and run an extension lead.

Why would one buy one? 

If you only have a limited need for a battery then they are a cheap option. You can currently get a nominal 2.4kWh capacity PPS for £1199 or £1119 (with a voucher code) which is cheaper than any installed battery option. Remember the PPS is not jus5 a battery, it includes the MPPT charge controller and inverter

They are portable so can be used inside or outside the house.

You can plug in a free standing solar panel directly to them if you want to generate your own (or some additional) PV.
They don’t need to be wired in to the house - you just plug appliances straight into the PPS. 
They have multiple DC outlets.
They provide a power cut back up. 

They have reasonable battery life. (Mine has a battery life of 2500 cycles, some have longer. I can’t see any means of measuring the number of cycles though.)

For me it was a combination of things. I wanted some form of power cut back up. (My electrician is going to put my boiler supply on a plug so I can have central heating when there is a power cut). I wanted to have the facility to time shift my PV generation for evening use and also have some limited option to charge on cheap rate electricity and use when rates are higher (my PPS is not ideal for this but others can charge faster). Finally I just wanted to play around with solar panels as I don’t have any south facing panels for winter. I have mounted a solar panel on a pallet with casters so I can follow the sun and use the battery to collect the generation. 

No, at around 50p per battery cycle (around 25p/kWh when my electricity costs me 13.3p) I am not expecting it to pay for itself, but I have satisfaction. I’ve just bought a second one for additional back up capacity.

Below is a link to a YouTube video from Anthony Dyer which finally convinced me that I should buy a PPS.
https://youtu.be/XEwhCDJp3os

Hi JKenH I need to get a Power Station for field measurements at work. I am looking at the 2.4kwh PowerOak unit you have. Are you still happy with it?  Do you think it will cope with been abused i.e., fully discharged and/or perhaps left without use for a few months?

JKenH

2nd_time_buyer said:

JKenH said:

I have made reference to my portable power station in other posts but as I believe these are very useful bits of kit for some people I thought a separate thread might be a good idea. 

In case any has not come across them a PPS consists of a an MPPT charge controller, a lithium battery and an inverter. Their primary use is for outdoor camping coupled with a portable solar panel but they have other uses,for instance providing power occasionally in an outbuilding such as a garage, summerhouse or home office where there is no mains supply. In the US it seems quite a few people use them for their off grid cabins. There are a wide range of battery sizes (from a couple of hundred Wh to over 3kWh and inverter outputs up to around 3kw. My PPS has a nominal capacity of 2.4kWh (just under 2kWh useable) and an output of 1kW (1.2kW) peak.

The first point I would like to make is that for most people a grid tied battery is a better option and the bigger the battery capacity you are after the better that option becomes. With some PPSs there is the option to add additional battery capacity but most smaller capacity ones are stand alone units so are not expandable. For some of us though a grid tied battery is not an option so a PPS gives us a cheap alternative to a professionally fully installed battery, albeit with much reduced functionality.

Some of the drawbacks:

Limited battery capacity unless you buy a more sophisticated model with expandable battery options and then it gets expensive. 

Limited charging rate - mine only charges at 210w from the grid or up to 500w from a solar panel so even on my GoFaster tariff I can only add 1kWh at cheap rate. It is though, a low enough charge rate to leave it on topping up during daylight hours.
Limited AC output potential. 

They cannot (generally) be connected to the house supply to cover overnight loads or supplement the grid supply when solar is low nor can they follow grid usage and only charge when there is spare PV.
There is some fan noise but you can put the PPS in another room and run an extension lead.

Why would one buy one? 

If you only have a limited need for a battery then they are a cheap option. You can currently get a nominal 2.4kWh capacity PPS for £1199 or £1119 (with a voucher code) which is cheaper than any installed battery option. Remember the PPS is not jus5 a battery, it includes the MPPT charge controller and inverter

They are portable so can be used inside or outside the house.

You can plug in a free standing solar panel directly to them if you want to generate your own (or some additional) PV.
They don’t need to be wired in to the house - you just plug appliances straight into the PPS. 
They have multiple DC outlets.
They provide a power cut back up. 

They have reasonable battery life. (Mine has a battery life of 2500 cycles, some have longer. I can’t see any means of measuring the number of cycles though.)

For me it was a combination of things. I wanted some form of power cut back up. (My electrician is going to put my boiler supply on a plug so I can have central heating when there is a power cut). I wanted to have the facility to time shift my PV generation for evening use and also have some limited option to charge on cheap rate electricity and use when rates are higher (my PPS is not ideal for this but others can charge faster). Finally I just wanted to play around with solar panels as I don’t have any south facing panels for winter. I have mounted a solar panel on a pallet with casters so I can follow the sun and use the battery to collect the generation. 

No, at around 50p per battery cycle (around 25p/kWh when my electricity costs me 13.3p) I am not expecting it to pay for itself, but I have satisfaction. I’ve just bought a second one for additional back up capacity.

Below is a link to a YouTube video from Anthony Dyer which finally convinced me that I should buy a PPS.
https://youtu.be/XEwhCDJp3os

Hi JKenH I need to get a Power Station for field measurements at work. I am looking at the 2.4kwh PowerOak unit you have. Are you still happy with it?  Do you think it will cope with been abused i.e., fully discharged and/or perhaps left without use for a few months?

Yes, still happy with mine, in fact I bought a second. I have found them very useful during Octopus saving sessions. I have been able to switch off the electricity at the consumer unit and run the central heating, fridge/freezers and router. Because I am still on a very cheap tariff 5p/13.3p I haven’t bothered charging overnight to use during the day solely to save a few pence as the purchase cost divided by the cycles 48p/cycle needs a difference of about 30p/kWh to break even. 

For your intended usage, the advice is I believe to fully charge if being left for 3 months. I have fully discharged mine at times but the PPSs are too new for me to tell if there has been any degradation as a result. I think the  weight is around 21kilos which is a bit heavy for my wife to carry around. but with the suitcase style packaging (carry handle on top) I cope fine. I wouldn’t want to walk half a mile with one, though.

I would like to see a faster charge rate (only 200watts from a 13A supply) and a higher discharge rate than the 1000watts but purely in terms of kWh/£ they are the best value PPS around. 

You can currently buy the EB240 at £1099.