Do I need solar?

[pophops]

We have an on-line mooring with no access to mains power.

The boat has one starter battery and two leisure batteries and our only way of charging them is by running the engine.

All our lighting is provided by incandesent "car" bulbs. Apart from the lights our only other electrical loads are a radio/CD player, water, shower and bilge pumps, a 12v hair dryer, 12v car vac. and phone chargers. We have a gas fridge and no TV, (we'd rather watch the sun go down).

The boat is used almost exclusively for short and moderate length cruises and I have never had an issue with lack of 12v power in the 3 years we had had her. I suppose what I want to know is 'do I need to update the lighting and should I get some sort of trickle charging system installed'? Or should I save my money and just continue to abuse the batteries and replace them when they finally die?

Would spending money on updating the lighting or buying solar be cost-effective?

(If this comes over as being 'smug', I'm sorry, I don't mean it to. I just wonder if we should carry on as we are or spend some money on updating things).

[Grace and Favour]

The first thing I'd do would be to change your bulbs to LED's

 

The second thing would be to fit some solar panels

 

Diesel will only ever become dearer.

 

I'm also lead to believe that as solar charges your batteries more slowly (and therefore better) it could/will extend the life of your batteries

[NB Lola]

Also depends on your disposable income.

 

Can you afford to replace your batteries after terminal abuse?

 

Do you accept the environmental impact on replacement ?

 

If the answer is yes, use away!

[Paul C]

The boat is used almost exclusively for short and moderate length cruises

 

Can you define what you mean by "short" and "moderate length". If you go on a moderate length cruise, how many hours is the engine running, and are you staying on the boat overnight etc?

[Guest]

We have an on-line mooring with no access to mains power.

The boat has one starter battery and two leisure batteries and our only way of charging them is by running the engine.

All our lighting is provided by incandesent "car" bulbs. Apart from the lights our only other electrical loads are a radio/CD player, water, shower and bilge pumps, a 12v hair dryer, 12v car vac. and phone chargers. We have a gas fridge and no TV, (we'd rather watch the sun go down).

The boat is used almost exclusively for short and moderate length cruises and I have never had an issue with lack of 12v power in the 3 years we had had her. I suppose what I want to know is 'do I need to update the lighting and should I get some sort of trickle charging system installed'? Or should I save my money and just continue to abuse the batteries and replace them when they finally die?

Would spending money on updating the lighting or buying solar be cost-effective?

(If this comes over as being 'smug', I'm sorry, I don't mean it to. I just wonder if we should carry on as we are or spend some money on updating things).

 

Some useful info. here when I asked a similar question a while ago.

 

We didn't go ahead at the time as we were on shore power and the setup I was considering was as a back up if that failed.

 

I do plan to follow it up this year as we too are on a mooring without shore power and I would like to think the batteries were getting a trickle charge during the times we are not on the boat. You don't have to spend a fortune if all you want to do is keep something going into the batteries, though you may want to consider more than just the single 50W panel I am getting.

 

Solar panels for beginners thread

[BargeeSpud]

If you're considering fitting solar panels, bear in mind security as you moor on-line. If you are moored on the towpath, then you'll need to fix them securely against theft whilst you're not aboard. Even if you're moored off-side, it is peace of mind to fix them anyway depending on the security of your mooring site.

 

We have probably one of the most secure off-side moorings anywhere, belonging to a security patrolled demolition company & I still have my panels securely fixed.

 

Like you, I only spend some weekends & holidays on my boat & I also had to charge my batteries with the engine or via a generator, almost on every visit. But since fitting solar panels, I've not had the need to do this other than for regular genny charging to give the batteries a proper multi-stage charge, about every couple of months.

Edited May 13, 2013 by Spuds

[pophops]

Can you define what you mean by "short" and "moderate length". If you go on a moderate length cruise, how many hours is the engine running, and are you staying on the boat overnight etc?

Short - 45min each way to the local pub

Moderate - 5 or 6 hours a day for 4 or 5 days a few times a year and staying aboard overnight.

Edited May 13, 2013 by pophops

[Paul C]

Short - 45min each way to the local pub

Moderate - 5 or 6 hours a day for 4 or 5 days a few times a year and staying aboard overnight.

 

Thanks, spot on info. I'd say you'd benefit a lot from solar. The reason being, on the short trips, the engine isn't running long enough to give a decent charge to the battery. On the moderate trips with an overnight stay, (I don't know your power audit so its an estimate, but an educated guess of one given the info you supplied in the OP) I'd say your 5-6 hours is recharging the batteries adequately.

 

The advantage of solar is that it gives a long, slow, moderate charge which is ideal for the long term health of batteries. And of course, its 'free' (on running costs, not capital costs).

[IainW]

The longer you are away from your boat, the less solar you will need as it has more time to recharge the battery bank while you are away. Plus if when you are actually at your boat you are cruising, you don't need to rely on solar then. Maybe look at dividing the total amp/hr of you bank (200ish?) by the average or minimum time you are away and working out how many amps you need to be firing in to your batteries while you are away. Then get panels that can do this...

[Arthur Brown]

OK it's worked for three years so it will likely continue to work, you don't actually need changes.

 

However I would look to fitting low energy lights (LED or CFL) as part of any update, as they use lots less electricity for their light output.

Again You cope without, so solar is an improvement not an essential. I'd look for a small panel for the starter battery -say 10w- to ensure that the natural self discharge doesn't stop you starting the engine. You could fit a small panel for the house battery estimated to cover the fixed loads -bilge pump in particular.

 

The aim being to prevent need for periods of stationary charging.

 

Diesel will never get cheaper

[Timleech]

The main benefit of some solar with your sort of usage is, I think, that you won't need to worry too much about leaving the boat with the batteries fully charged, the solar input will top them up over the course of a few days. Leaving batteries discharged is bad. Suppose you spend a night on board and then have to leave the boat in the morning without a run?

You shouldn't need a massive amount, maybe something between 50 and 100W?

Re the theft issue, maybe consider semi-flexible panels bonded to the roof? They are more expensive per watt, but much less obtrusive.

 

Yes do change the lights to LED, definitely.

 

Tim

[Biggles]

I haven't run my engine or generator for over a month now simply to charge the batteries. I am aboard 3-4 days a week. My biggest draw is a 240v fridge freezer which I don't bother with if I'm here on my own working as I prefer to get fresh stuff daily and milk and beer stay cool enough in the bilge.

 

I have 500w solar and MPPT into 1180a/h and my batteries are topped up by lunch from about this time time of year. The inverter is left on all the time I'm on the boat and we have.

 

I would say yes, but theres no need to go mad if all you want to do is keep the batteries topped up while away.

 

BTW in winter or before the solar really kicks in I have to run the genny about 2-3 hours every couple of days.

[smileypete]

As well as fitting LED lights it'd be worth fitting a digital voltmeter if you don't already have one, to allow at least some sort of batt monitoring. If you don't mind a long wait for shipping, they can be had for a few pounds on Ebay from suppliers in Asia.

 

cheers, Pete.

~smpt~

[BD3Bill]

Hi Pophops

 

I have the same amount of batteries as you and roughly the same usage pattern.

 

Do lash out on the LED bulbs.

 

I have a 40w Bosch panel and basic controller and this suits very well. It is about the size of the sliding hatch, slightly smaller 600x550mm.

 

£120 from Photonic Universe on eBay.

They do a dual battery bank controller option,

I have just the leisure batts on solar.

 

A dual controller and 50w panel will do you nicely to maintain 1 starter and 2 leisure batteries.

 

Agree with Smileypete:

£9 digital voltmeter plugged into cigar lighter socket monitors voltage state.

 

When aboard we have enough power to run the fridge for the daytime. We don't have a telly though.

Cheers

Bill

Edited May 21, 2013 by BD3Bill

[Rebotco]

The main benefit of some solar with your sort of usage is, I think, that you won't need to worry too much about leaving the boat with the batteries fully charged, the solar input will top them up over the course of a few days. Leaving batteries discharged is bad. Suppose you spend a night on board and then have to leave the boat in the morning without a run?

You shouldn't need a massive amount, maybe something between 50 and 100W?

Re the theft issue, maybe consider semi-flexible panels bonded to the roof? They are more expensive per watt, but much less obtrusive.

 

Yes do change the lights to LED, definitely.

 

Tim

 

 

Yes I would agree with this.

 

I have similar usage as you but have fitted a 100 watt solar panel. Its so much more relaxing going to the boat knowing things will work and the batteries won't be flat (especially the auto bilge pump)!

I also have used the flexible stick on variety to minimise the risk of getting them nicked. It cost a couple of hundred quid, but worth it for the peace of mind, and extended battery life. I shall next change to LED lighting when they get cheaper and as the fluorecents naturally die off.

 

Still, if its working OK for you, there's no rush, and slow improvements are the way to go.

[Doodlebug]

As has already been said, you need to change your lighting to led. Ebay is the place to go for all things electrical.

 

Dont be afraid to buy from china. I have been doing it for years, and paypal protects you if anything were to go wrong. Downside is a month delivery.

 

In terms of solar panels, only go for monocrystaline if you can. They are far more effective. And again, look on ebay.

 

A note on lighting, we have a 5m led strip from ebay that looks really good and gives alot of lighting. Uses about 2 amps but does a very good job.

 

Hope that helps