Best Electric Generator For Back-Up Power.

[Dave Hounddriver]

Some very good information here but how much applies in the Philippines since we are very limited on choices of generators, inverters and batteries?

I have had no trouble finding what I need.  The prices are a bit steep for me though.  If you have found a suggestion here that interests you, and you cannot find the parts/equipment you need, I would encourage you to start a thread about 'where to find' what it is you need.

 

Lots of helpful people on this forum.

[robert k]

Americano, like most problems, I think it's a matter of money and decent engineering. If it's just for the odd brownout, a battery bank of 12, 100 amp hour car batteries and an inverter charger would probably see you through. For catastrophic loss of power, you need a generator which can sustain you for several days, or both. How well whatever you decide to do works may be directly related to to how much money you spend. I believe that the batteries may add some efficiency to a generator / power system but they add to the maintainance and cost. I would just buy a generator unless your power outages are weekly and greater than 1 day because trying to make the system more efficient is going to add complexity and cost that may not be recovered by the seldom used greater efficiency as backup power.

 

Batteries or generator, I would probably be building a CHB outbuilding to go with it, most generators are not very quiet and the batteries would need a home where they can outgas and both need a secure place where they won't walk off.

[not so old china hand]

I would just buy a generator unless your power outages are weekly and greater than 1 day because trying to make the system more efficient is going to add complexity and cost that may not be recovered by the seldom used greater efficiency as backup power.

 

 

I agree with Robert that the simplest solution is just to buy a petrol generator. I would keep the wiring simple by just using a good heavy-duty extension cable - unless you need to power appliances in several different rooms. Wiring a generator into a house's mains circuit could be risky - unless you know how to do it correctly. I can't speak from experience of household electrics. On the junk the 220v generators were wired through the inverter, which automatically detected when ac current was available and switched this through to the ac circuit.

 

However if you only need to keep electronics such as DSL modems running so you can stay connected to the internet - and you use a laptop or iPad - a relatively small battery and a low output inverter  would do the job. (I assume the Philippines telecomms suppliers do have their own back-up power to keep their services running through brownouts).

 

In fact if keeping your internet running, recharging phones and laptops and suppling some light was all the battery was required to do, you might be able to manage with just 12v dc, using the type of adaptors designed to be used in a car. For light you could use 12v LED bulbs, which only draw a minute current.

 

Whatever you decide I would strongly recommend using proper deep cycle batteries. A car battery will get knackered very quickly if you use it as a power source. I learnt this the hard way by writing-off several so-called heavy duty truck batteries. I then did the research I should have done earlier (when all else fails RTFM.) :1 (103):

 

I discovered that car batteries are optimised to crank out hundreds of amps for a short period. To do this they have thin, closely spaced plates. Deep cycling the battery (ie drawing down more than 20% of the battery's capacity) rapidly causes the plates to buckle and loose the lead sulfate in the cathodes. Result a dead battery. I then did what I should have done earlier and replaced the batteries in both the starter and the domestic battery banks with four 180 amp hour deep cycle AGM batteries.

 

Using AGM batteries, or Gel batteries as Lyno 47 does on the RVs he kits out, has the advantage that they don't gas and don't spill so they can be safely used indoors.

 

I also agree with Robert that a dedicated generator/battery shed is a good idea. One of the projects on the junk that didn't get started was building a sound-proofed housing for the Honda genny.

 

Cheers Terry

Edited May 21, 2014 by not so old china hand

[Dave Hounddriver]

I agree with Robert that the simplest solution is just to buy a petrol generator.

 

Been there, done that, and got the petrol bills to prove it.  The cost of petrol to run a generator big enough to supply the power I customarily receive through the power grid was about 100 pesos per hour for every hour I had the 6,5 kv machine running.  That cost is one reason I am still looking at alternatives in case I have to go through another extended period of power outage caused by a typhoon, earthquake or some other disaster.  Lack off availability of petrol during such a crisis is another reason to look for alternatives.

[Jake]

 

I would just buy a generator unless your power outages are weekly and greater than 1 day because trying to make the system more efficient is going to add complexity and cost that may not be recovered by the seldom used greater efficiency as backup power.

 

Whatever you decide I would strongly recommend using proper deep cycle batteries. A car battery will get knackered very quickly if you use it as a power source. I learnt this the hard way by writing-off several so-called heavy duty truck batteries. I then did the research I should have done earlier (when all else fails RTFM.) :1 (103):

 

I discovered that car batteries are optimised to crank out hundreds of amps for a short period. To do this they have thin, closely spaced plates. Deep cycling the battery (ie drawing down more than 20% of the battery's capacity) rapidly causes the plates to buckle and loose the lead sulfate in the cathodes. Result a dead battery. I then did what I should have done earlier and replaced the batteries in both the starter and the domestic battery banks with four 180 amp hour deep cycle AGM batteries.

 

Using AGM batteries, or Gel batteries as Lyno 47 does on the RVs he kits out, has the advantage that they don't gas and don't spill so they can be safely used indoors.

 

I also agree with Robert that a dedicated generator/battery shed is a good idea. One of the projects on the junk that didn't get started was building a sound-proofed housing for the Honda genny.

 

Cheers Terry

 

Triple LIKE Terry!

Edited May 21, 2014 by Jake
highlight comment

[robert k]

I will take a wild guess and assume that Dave Houndriver has an aircooled 6.5kw generator running at half capacity which is about as efficient as it's going to get for an air cooled generator at 100 pisos per hour for fuel. You have to remember that aircooled engines have good power to weight ratio and generally are less expensive to build, they were not chosen because they were the most efficient. Daves generator also probably has an alternator that has has to generate a field to produce power, the least expensive kind to build, and not a permanent magnet alternator which does not have to generate a power hogging electromagnetic field before it can start making power.

 

As far as I know nobody makes a small, water cooled, permanent magnet alternator / generator.

 

Without large system start up costs, solar, wind, battery bank, custom build a generator, the only way I think you are going to see much savings over what you have now is to use the generator less.

 

I see air conditioning as the killer, you could use a generator with half the output and possibly half the cost to run if all you were running were a refrigerator, fans, lights, television, computer with possibly one battery and inverter to run the refrigerator, your power draw could be pretty small. If you needed continuous air conditioning, maybe you could mount a Thermo King unit off of a truck trailer on your house that has it's own engine and drives the a/c compressor directly so you don't have the loss of converting fuel to motive power to electricity back to motive power to drive the compressor. If there is a solution anywhere, it's going to be a creative one. There may be no cost effective solution unless you live on a mountain with a large head of water nearby, but that would be for a hydroelectric thread.

[Jake]

I will take a wild guess and assume that Dave Houndriver has an aircooled 6.5kw generator running at half capacity which is about as efficient as it's going to get for an air cooled generator at 100 pisos per hour for fuel. You have to remember that aircooled engines have good power to weight ratio and generally are less expensive to build, they were not chosen because they were the most efficient. Daves generator also probably has an alternator that has has to generate a field to produce power, the least expensive kind to build, and not a permanent magnet alternator which does not have to generate a power hogging electromagnetic field before it can start making power.

 

As far as I know nobody makes a small, water cooled, permanent magnet alternator / generator.

 

Without large system start up costs, solar, wind, battery bank, custom build a generator, the only way I think you are going to see much savings over what you have now is to use the generator less.

 

I see air conditioning as the killer, you could use a generator with half the output and possibly half the cost to run if all you were running were a refrigerator, fans, lights, television, computer with possibly one battery and inverter to run the refrigerator, your power draw could be pretty small. If you needed continuous air conditioning, maybe you could mount a Thermo King unit off of a truck trailer on your house that has it's own engine and drives the a/c compressor directly so you don't have the loss of converting fuel to motive power to electricity back to motive power to drive the compressor. If there is a solution anywhere, it's going to be a creative one. There may be no cost effective solution unless you live on a mountain with a large head of water nearby, but that would be for a hydroelectric thread.

Dang Robert,

 

I can readily see your other sides: surveyor, earth mover, custom builder and off gridder.  I would love to

see your fortified home....he, he.  Obviously, you learned all the basic and advance ways on how to move

a couple battalions advancing the battle line.  Power, security, comms, infrastructure -- you don't want to

piss off a general because power went off at his tent.  What does the US Army recommend these days for

a nice portable (light weight) genny?  

[robert k]

Jake, as far as I know, the army does it the old fashioned way. I hope to God they have replaced those Chrysler marine 1.5kw generators. Years ago I heard of some people buying some surplus hydroelectric generators that the army used to use, supplied their needs and they retired off the money they made selling the excess electricity, but you need the river with sufficient flow first.

 

I never had to supply power for a generals tent, they usually tried to keep me away from high ranking officers after my first conversation with a general. We did however adopt some guys who had an airconditioned optics van. I found an unsecured 5kw quiet water cooled electric start trailer mounted generator, mostly for their benefit. I can't swear to it but I believe it used less fuel than our 1.5kw air cooled Chrysler marine generator which was so loud you couln't hear yourself think.

 

I mentioned earlier about the powermate brand used to make a 2.8 kw generator that was almost twice as efficient as their 3 kw generator there must have been a tipping point there where a more powerful engine was required. If I could, I might buy two of those and run only one unless I needed the other to meet peake demand. It would also give some redundency if one failed, if you could find two of them.

 

The ultimate for a small amount of portable power would be one of those generators powered by an Echo weedeater motor, it only produced 900 watts but you could pick it up with two fingers and hold it at arms length, unlike the heavy small 2 stroke generators that can be had.

Edited May 21, 2014 by robert k

[Jake]

Jake, as far as I know, the army does it the old fashioned way. I hope to God they have replaced those Chrysler marine 1.5kw generators. Years ago I heard of some people buying some surplus hydroelectric generators that the army used to use, supplied their needs and they retired off the money they made selling the excess electricity, but you need the river with sufficient flow first.

 

I never had to supply power for a generals tent, they usually tried to keep me away from high ranking officers after my first conversation with a general. We did however adopt some guys who had an airconditioned optics van. I found an unsecured 5kw quiet water cooled electric start trailer mounted generator, mostly for their benefit. I can't swear to it but I believe it used less fuel than our 1.5kw air cooled Chrysler marine generator which was so loud you couln't hear yourself think.

 

I mentioned earlier about the powermate brand used to make a 2.8 kw generator that was almost twice as efficient as their 3 kw generator there must have been a tipping point there where a more powerful engine was required. If I could, I might buy two of those and run only one unless I needed the other to meet peake demand. It would also give some redundency if one failed, if you could find two of them.

 

The ultimate for a small amount of portable power would be one of those generators powered by an Echo weedeater motor, it only produced 900 watts but you could pick it up with two fingers and hold it at arms length, unlike the heavy small 2 stroke generators that can be had.

Hey Sergeant Major,

 

There are so many configurations mentioned and thank you guys for keeping less technical for old folks

like me to better understand the whole system.  While we search for locally made genny or imported to

the Philippine market, I would like to discuss various scenarios like a super typhoon forcing you and your

family to evacuate.  What would you carry with you regarding back up power?

 

I like the idea of portability -- lightweight, one man carry.  Perhaps carry a 12vdc AGM battery, a small

hand carried genny and power inverter-converter.  That way, I can still have my pina coladas and halo-

halo during times of emergencies.....he, he.

 

And by going light weight, I can carry additional rounds of ammo (about 5000 7.62 rounds) for my M-60

for persuasion purposes.  

 

Sabot up -- Jake

PS -- I just promoted your butt to E-9 for a job well done.  

Edited May 22, 2014 by Jake
field promotion

[scott h]

tounge in cheek here,,,but the best way to avoid brown outs is move to metro manila,,,,have had maybe one 2 hour brown out in 2 years. :unsure: