Practical Solar Energy
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Ken Ebbage
Oct 29, 2009, 2:14:54 AM10/29/09
to St Albans Environment
After my humble experiments with a 60W solar panel, it is great to see
a practical description of a full scale house conversion here:
http://www.christian-ecology.org.uk/solar-pv-tiles-baildon.htm
Does anyone have experience on this sort of level in our Diocese?
Ken
a practical description of a full scale house conversion here:
http://www.christian-ecology.org.uk/solar-pv-tiles-baildon.htm
Does anyone have experience on this sort of level in our Diocese?
Ken
Roger Courtney
Oct 29, 2009, 6:53:33 AM10/29/09
to st-albans-...@googlegroups.com
This is a useful account of a PV installation, particularly as the
introduction of feed-in tariffs will now give considerable encouragement to
the installation of such systems - and there is currently an especially
favourable window since the present grant system runs until next April and
the feed-in tariffs will apply to systems installed between now and then.
Taking account of cost savings and the feed-in tariff, the value of each kWh
generated will be around 45p.
The figures quoted bear out the accepted annual generation figure of around
800kWh per peak kW of the installation (which will be worth around £360). It
is not clear how large the installation was. At around 12-15% efficiency of
conversion, a 1kWp installation would take about 7-8 square metres of roof,
assuming that it was inclined and orientated to the south. So this one
rated at 2.4kWp was probably around 20 square metres - probably larger than
most people could install comfortably on their roofs.
The figure that I would challenge is the pay-back time for the embodied
energy of the installation. This seems much shorter than commonly accepted
figures and I wonder whether it is just referring to the energy used in
manufacturing the cells. Tracking everything from start (extraction of
materials) through processing, transport and installation (eg fuel used by
installers) and allowing for factors like battery replacement every 5-7
years results in a much longer pay-back time, although estimates vary
according to the assumptions made and of course with the country where the
installation is located. I note that the comment comes from a German
source - southern Germany tends to have clear, sunny winters and so a PV
installation will produce more energy over the year than in the same size of
installation in the UK. I accept that some of the inputs might be discounted
in this case because the building was being re-roofed anyway but most
installations will be additions to existing roofs. No doubt with larger
manufacturing volumes and new PV technologies the pay-back will improve. The
new tariffs make the installation of a PV system a much more attractive
proposition to householders and churches and that will feed through into
enhanced market demand, more efficient production methods and lower prices.
Roger Courtney
introduction of feed-in tariffs will now give considerable encouragement to
the installation of such systems - and there is currently an especially
favourable window since the present grant system runs until next April and
the feed-in tariffs will apply to systems installed between now and then.
Taking account of cost savings and the feed-in tariff, the value of each kWh
generated will be around 45p.
The figures quoted bear out the accepted annual generation figure of around
800kWh per peak kW of the installation (which will be worth around £360). It
is not clear how large the installation was. At around 12-15% efficiency of
conversion, a 1kWp installation would take about 7-8 square metres of roof,
assuming that it was inclined and orientated to the south. So this one
rated at 2.4kWp was probably around 20 square metres - probably larger than
most people could install comfortably on their roofs.
The figure that I would challenge is the pay-back time for the embodied
energy of the installation. This seems much shorter than commonly accepted
figures and I wonder whether it is just referring to the energy used in
manufacturing the cells. Tracking everything from start (extraction of
materials) through processing, transport and installation (eg fuel used by
installers) and allowing for factors like battery replacement every 5-7
years results in a much longer pay-back time, although estimates vary
according to the assumptions made and of course with the country where the
installation is located. I note that the comment comes from a German
source - southern Germany tends to have clear, sunny winters and so a PV
installation will produce more energy over the year than in the same size of
installation in the UK. I accept that some of the inputs might be discounted
in this case because the building was being re-roofed anyway but most
installations will be additions to existing roofs. No doubt with larger
manufacturing volumes and new PV technologies the pay-back will improve. The
new tariffs make the installation of a PV system a much more attractive
proposition to householders and churches and that will feed through into
enhanced market demand, more efficient production methods and lower prices.
Roger Courtney
RE4All
Nov 16, 2009, 6:45:10 PM11/16/09
to St Albans Environment
I think the biggest challenge lies in concentrating the solar energy.
The success of solar power as a dominant source of usable energy will
lies in the fact on how much the technology can better in the solar
concentrations.
VR
http://blog.valopia.com/blog/post/2009/11/15/Business-of-capturing-maximum-solar-energy.aspx
On Oct 29, 4:53 am, "Roger Courtney" <roger.court...@ntlworld.com>
wrote:
> figures and I wonder whether it is just referring to theenergyused in
>
> - Show quoted text -
The success of solar power as a dominant source of usable energy will
lies in the fact on how much the technology can better in the solar
concentrations.
VR
http://blog.valopia.com/blog/post/2009/11/15/Business-of-capturing-maximum-solar-energy.aspx
On Oct 29, 4:53 am, "Roger Courtney" <roger.court...@ntlworld.com>
wrote:
> This is a useful account of a PV installation, particularly as the
> introduction of feed-in tariffs will now give considerable encouragement to
> the installation of such systems - and there is currently an especially
> favourable window since the present grant system runs until next April and
> the feed-in tariffs will apply to systems installed between now and then.
> Taking account of cost savings and the feed-in tariff, the value of each kWh
> generated will be around 45p.
>
> The figures quoted bear out the accepted annual generation figure of around
> 800kWh per peak kW of the installation (which will be worth around £360). It
> is not clear how large the installation was. At around 12-15% efficiency of
> conversion, a 1kWp installation would take about 7-8 square metres of roof,
> assuming that it was inclined and orientated to the south. So this one
> rated at 2.4kWp was probably around 20 square metres - probably larger than
> most people could install comfortably on their roofs.
>
> The figure that I would challenge is the pay-back time for the embodiedenergyof the installation. This seems much shorter than commonly accepted
> introduction of feed-in tariffs will now give considerable encouragement to
> the installation of such systems - and there is currently an especially
> favourable window since the present grant system runs until next April and
> the feed-in tariffs will apply to systems installed between now and then.
> Taking account of cost savings and the feed-in tariff, the value of each kWh
> generated will be around 45p.
>
> The figures quoted bear out the accepted annual generation figure of around
> 800kWh per peak kW of the installation (which will be worth around £360). It
> is not clear how large the installation was. At around 12-15% efficiency of
> conversion, a 1kWp installation would take about 7-8 square metres of roof,
> assuming that it was inclined and orientated to the south. So this one
> rated at 2.4kWp was probably around 20 square metres - probably larger than
> most people could install comfortably on their roofs.
>
> figures and I wonder whether it is just referring to theenergyused in
> manufacturing the cells. Tracking everything from start (extraction of
> materials) through processing, transport and installation (eg fuel used by
> installers) and allowing for factors like battery replacement every 5-7
> years results in a much longer pay-back time, although estimates vary
> according to the assumptions made and of course with the country where the
> installation is located. I note that the comment comes from a German
> source - southern Germany tends to have clear, sunny winters and so a PV
> installation will produce moreenergyover the year than in the same size of
> materials) through processing, transport and installation (eg fuel used by
> installers) and allowing for factors like battery replacement every 5-7
> years results in a much longer pay-back time, although estimates vary
> according to the assumptions made and of course with the country where the
> installation is located. I note that the comment comes from a German
> source - southern Germany tends to have clear, sunny winters and so a PV
> installation in the UK. I accept that some of the inputs might be discounted
> in this case because the building was being re-roofed anyway but most
> installations will be additions to existing roofs. No doubt with larger
> manufacturing volumes and new PV technologies the pay-back will improve. The
> new tariffs make the installation of a PV system a much more attractive
> proposition to householders and churches and that will feed through into
> enhanced market demand, more efficient production methods and lower prices.
>
> Roger Courtney
>
>
>
> ----- Original Message -----
> From: "Ken Ebbage" <ken.ebb...@pentana.com>
> To: "St Albans Environment" <st-albans-...@googlegroups.com>
> Sent: Thursday, October 29, 2009 6:14 AM
> Subject: [St Albans Environment] PracticalSolarEnergy
>
> > After my humble experiments with a 60Wsolarpanel, it is great to see
> in this case because the building was being re-roofed anyway but most
> installations will be additions to existing roofs. No doubt with larger
> manufacturing volumes and new PV technologies the pay-back will improve. The
> new tariffs make the installation of a PV system a much more attractive
> proposition to householders and churches and that will feed through into
> enhanced market demand, more efficient production methods and lower prices.
>
> Roger Courtney
>
>
>
> ----- Original Message -----
> From: "Ken Ebbage" <ken.ebb...@pentana.com>
> To: "St Albans Environment" <st-albans-...@googlegroups.com>
> Sent: Thursday, October 29, 2009 6:14 AM
> Subject: [St Albans Environment] PracticalSolarEnergy
>
> > a practical description of a full scale house conversion here:
>
> >http://www.christian-ecology.org.uk/solar-pv-tiles-baildon.htm
>
> > Does anyone have experience on this sort of level in our Diocese?
>
> > Ken- Hide quoted text -
>
> >http://www.christian-ecology.org.uk/solar-pv-tiles-baildon.htm
>
> > Does anyone have experience on this sort of level in our Diocese?
>
>
> - Show quoted text -
Roger Courtney
Nov 17, 2009, 4:06:07 AM11/17/09
to st-albans-...@googlegroups.com
Unfortunately, a high proportion of sunlight in the UK is diffuse, in
contrast to regions such as California and desert areas where it is
predominantly direct. Concentrating collectors work with direct radiation
and, as Chris Goodall commented at the Diocesan Environmental Conference on
Saturday, they aren't suited to the UK.
contrast to regions such as California and desert areas where it is
predominantly direct. Concentrating collectors work with direct radiation
and, as Chris Goodall commented at the Diocesan Environmental Conference on
Saturday, they aren't suited to the UK.
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