Archive for March, 2017

Cheap 10A and 20A MPPT controllers

Monday, March 27th, 2017

Now that Spring is poking her head out of the clouds, it’s absolutely the best time to invest in a bit of solar. And all solar installations need a controller which, if you want MPPT technology – and you may not know it but yes, you do, can be the most expensive part of the install.

There are two types of solar controller PWM, the standard, cheap offering, around £15 from Maplins in Bath, and MPPT, of which it is usually recommended to go for a Tracer, £65 from Bimble Solar. MPPT can offer a substantial increase in power harvested by matching the panels and batteries to the best voltage for maximum power (MPPT = Maximum Power Point Tracking )*. By contrast PWM simply switches off part of the time to avoid over-voltage. Going a bit techie, this means that the greater the difference between the VOC of the panel and the voltage of your battery (12V–14.8V) the more power is wasted whereas with MPPT you can string panels in series up to the maximum input voltage of the controller without losing power. The cheapest solar panels are those used for domestic arrays and are generally around 36V which either won’t work or waste most of their power with a PWM controller.

You have to be careful when looking for an MPPT controller, there are a lot of cheap solar controllers on eBay claiming to be MPPT which are, in fact PWM, but this model checks out as a genuine MPPT at around £20 to £25:

http://www.youtube.com/watch?v=05IcvuI7kJ8

Charge voltage is fixed at 14.7V which may be a little high for some, though not high enough to properly charge or equalise traction batts, but will give them more than a tickle. Max solar input is 50V.

A couple of links for these on Ebay:

http://www.ebay.co.uk/itm/MPPT-Solar-Charger-Controller-12V-24VDC-10A-20A-Battery-Regulator-USB-5V-Output-/142188324794
http://www.ebay.co.uk/itm/5A-10A-12V-24V-MPPT-Solar-Panel-Regulator-Charge-Controller-100V-Input-DC-USB-JS-/181861868553

Not as good as the latest Tracers and may be not as reliable, but possibly a good budget option for a small setup.

From Bimble Solar’s website

PWM vs MPPT charge controller test

We often get asked about the actual difference you get between an MPPT and a PWM controller so we setup a side by side test using our Yingli part used panels onto 2 separate 12V batteries, 1 with a PWM controller and one with our Tracer MPPT. Panels were set-up side by side angled south.

With early March sun the MPPT was giving 3.7A into the batteries while the PWM gave 2.5A which was 32% lower than the MPPT.

In cloudy conditions the MPPT was giving 1A when the PWM was giving 0.8A (20% lower with PWM)

Both charged the batteries well, but 20%-32% more power was gained by using the MPPT.

http://www.bimblesolar.com/beginnersguide#mpptpwm

 

(with thanks to Smiley Pete on CWDF for spotting it)

Visitor moorings at Seend bottom lock shortened following complaint

Wednesday, March 22nd, 2017

Following a complaint to K&A Manager Mark Evans, CRT has reduced the 48-hour visitor moorings below Seend bottom lock (lock 17) to the length recommended by the Kennet and Avon Visitor Mooring Review – Bath to Foxhangers in March 2015.

Despite a number of boaters contacting CRT about this, it took more than 7 months for the error to be corrected. The error was first reported to CRT in July 2016.

Earlier in 2016, CRT put up signs at the visitor moorings below lock 17 that extended these 48-hour visitor moorings by approximately 200 metres westward from the western end of the purpose-built length of visitor moorings right up to the culvert.

This was contrary to the Visitor Mooring Review, which recommended that this length of visitor mooring should be shortened so that it only covered the stretch with mooring rings. The remaining space should have reverted to 14 days in July 2015 for a trial period until September 2015.

This was done without any consultation with users which is contrary to CRT’s Short Term Moorings Framework for Change dated March 2015, which states on page 1 that before making any changes to visitor moorings, waterway managers should:

“Conduct quantitative monitoring of craft that use the mooring and local area over a length of time, taking into account various factors including time of day, time of year, weather and other such influencing factors

Consult with all those potentially affected by any changes, from local & visiting boaters to local retailers including marina operators and the hire boat industry

Pilot the potential changes over a period of time gathering data and feedback, allowing the proposals to be amended as required

Inform visitors and those affected of any changes in a meaningful, clear and consistent way that ensures confusion is avoided”.

There was no evidence that any of the above steps had been followed by CRT before making the change.

Although the complaint has been remedied, CRT has yet to explain either why the Short Term Moorings Framework for Change was not followed or provided proof that these steps were followed and that the evidence gathered justified the change that was made last year.

The correct location of the visitor moorings - from this point to the lock

The correct location of the visitor moorings – from this point to the lock

See also

http://kanda.boatingcommunity.org.uk/crt-makes-changes-to-ka-visitor-moorings-without-consultation/

http://kanda.boatingcommunity.org.uk/visitor-mooring-review-recommendations-to-be-trialled-from-july-to-october-send-your-comments-now/

http://kanda.boatingcommunity.org.uk/liveaboards-secure-representation-in-bath-devizes-visitor-mooring-review/

http://kanda.boatingcommunity.org.uk/visitor-moorings-to-become-14-days-in-winter/

CRT Trustees’ invitation to reception, Bath, 22nd March

Sunday, March 19th, 2017

Boats Are Homes campaign stall in Bradford on Avon, Sat 18th March

Friday, March 10th, 2017

Liveaboard boaters on the K&A are to hold an information and campaign stall in Lamb Yard, Bradford on Avon BA15 1FG on Saturday 18th March 2017 from 10am to 4pm.

Read more…

K&A boater wins Article 8 case against CRT in Court of Appeal in landmark judgement for boat dwellers

Wednesday, March 8th, 2017

K&A boater Matthew Jones yesterday won his appeal against CRT’s attempt to strike out the Article 8 elements of his defence against eviction from CRT’s waterways under Section 8 of the British Waterways Act 1983. The case will now be remitted back to Bristol County Court where Mr Jones will be able to put his Article 8 arguments in full. Mr Jones’s solicitor Community Law Partnership writes:

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Boat Fire Safety Talk, Pewsey Wharf, 14th March

Tuesday, March 7th, 2017

There will be a boat fire safety talk by Dorset and Wiltshire Fire and Rescue Service on Tuesday 14th March 2017 at 7.30pm at the Waterfront, Pewsey Wharf SN9 5NU.

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K&A boaters action group, 13th March, Bradford on Avon

Monday, March 6th, 2017

The next meeting of the K&A boaters’ action group will be on Monday March 13th 2017 at 7.30pm at the Canal Tavern, 49 Frome Rd, Bradford-on-Avon, BA15 1LE.

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National Boats Are Homes demonstration, 8th April

Saturday, March 4th, 2017

There will be a national Boats Are Homes demonstration in London on Saturday 8th April 2017. Transport will be available from the K&A – contact info@boatingcommunity.org.uk or 07928 078208.

Boats Are Homes demo poster 8-4-17

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