Help with calculations and requirements

RenwableSavings

Hi, I'm making a calculator for savings and earnings for going renewable. I need realistic feedback of how these systems have operated in the past for people. Like, which is better, flat plate or tube solar thermal collectors?

I also want to create a suitability questionnaire with realistic advice to users about whether a technology is right for them. I am currently in the process of creating flow diagrams for them.

Any help would be much appreciated

Cardew

Welcome to the forum. May we ask why you are producing such a calculator.

In any case, why ask people when all the information is freely available on the web. How would people know which is better, evacuated tube or flat plate unless they were running back to back tests on their roof.

If you look at some of the threads on solar thermal you will find the links to a Government sponsored trial of 8 systems(both evacuated tube and flat plate) See:

This is an exaustive trial of 8 systems carried out for the Dti at Cranfield? *

http://www.dti.gov.uk/files/file16826.pdf

*
For those not conversant with the units used!
For the 8 systems tested(evacuated Tube and Flat plate) the annual output ranged from 3440 MJ(megajoules) equal to 955kWh to 4,820MJ(1,339kWh)
However from that total had to be deducted the ‘parasitic’ energy to run the pump and electronics. This ranged between zero and 390MJ(108kWh) pa. This of course is daytime rate electricity.
The average for the 8 systems was just over 1,000kWh per year.

Asking people what they save from solar thermal will elicit some absolutely stupid responses - if posts on this and other forums is anything to go by.

People having been conned into spending thousands of pounds by solar salesmen for the most disreputable industry in UK, are just not prepared to accept that £50 a year or so(if they are lucky) is the savings they are making. In the same way, loads of people on this and other forums are convinced that strapping a magnet on the fuel lines of their car or oil CH reduces consumption by 30%!!

Read WHICH and Energy Saving Trust for confirmation of typical savings.

I would also suggest that any work you do now on a calculator will be nugatory as the outcome of the RHI proposals will not be known until the Autumn.

Jon_Tiffany

For most people the biggest energy cost is space heating, best to make sure you have good insulation first.

RenwableSavings

Cardew wrote: »

Welcome to the forum. May we ask why you are producing such a calculator.

In any case, why ask people when all the information is freely available on the web. How would people know which is better, evacuated tube or flat plate unless they were running back to back tests on their roof.

If you look at some of the threads on solar thermal you will find the links to a Government sponsored trial of 8 systems(both evacuated tube and flat plate) See:



Asking people what they save from solar thermal will elicit some absolutely stupid responses - if posts on this and other forums is anything to go by.

People having been conned into spending thousands of pounds by solar salesmen for the most disreputable industry in UK, are just not prepared to accept that £50 a year or so(if they are lucky) is the savings they are making. In the same way, loads of people on this and other forums are convinced that strapping a magnet on the fuel lines of their car or oil CH reduces consumption by 30%!!

Read WHICH and Energy Saving Trust for confirmation of typical savings.

I would also suggest that any work you do now on a calculator will be nugatory as the outcome of the RHI proposals will not be known until the Autumn.

This is the reason I have started this thread. My aim is to produce a website app which will be the most comprehensive financial estimate and suitability questionnaires on the web. In the future it may be more of a comparison website. It will feature, wind turbines, Solar PV, solar thermal, rainwater harvesting, heat pumps and biomass.

My business model is to offer this service (calculator & questionnaire) for free and then if users wish they can get a free desktop survey and competitive quote from MCS certified installers.

But to offer a good service I need to be sure that what I am saying is correct and people will not be ripped off. I want people to be sure that it is right for them. I would like feedback for what I've got so far.

Ultimately I would like to help the industry to grow and become more cost effective because our future needs will rely on renewables.

Cardew

Someone came up with exactly this idea on MSE a few weeks ago and got all his posts removed, as you need to get permission from MSE.

Essentially your business model is to garner contacts to sell to the alternative energy industry.

If you want to get information on merits and costs of solar, wind turbines etc etc it is all available on the web. So why do you want customer's experiences?

On the web are exaustive trials, under controlled conditions, of solar systems and wind turbines.

The output in kWh of xkWp of solar PV panels depends on where the panels are in UK and the orientation of the panel - again loads of websites that enable you to get accurate estimations.

There have been scores of posts on MSE and other forums where people give their experiences of, say, solar thermal. Their posts are along the lines of "last year my gas bill was £1,000, then I fitted solar thermal and it is now £52 so it has saved me £948"!!

You say you want to ensure information is correct. How would you verify any results from such responses? Sort out which posts were from solar/wind turbine salesmen?

RenwableSavings

Cardew, yes it was me. How do I go about getting permission from MSE?

I was after feedback more than trying to create awareness as I want to get it right before marketing it.

I think there is a need for such a site. One that can bring all the technologies together to compare and check suitability for each technology.

I know there are other sites out there that can help and I am investigating them too, but I happen to be a frequent user of this site myself and thought some people might like the idea.

I'm starting out, just passed my IT degree and was after advice. I will choose another forum if this is inappropriate.

Cardew

RenwableSavings wrote: »

Cardew, yes it was me. How do I go about getting permission from MSE?

I was after feedback more than trying to create awareness as I want to get it right before marketing it.

I think there is a need for such a site. One that can bring all the technologies together to compare and check suitability for each technology.

I know there are other sites out there that can help and I am investigating them too, but I happen to be a frequent user of this site myself and thought some people might like the idea.

I'm starting out, just passed my IT degree and was after advice. I will choose another forum if this is inappropriate.

Much as I admire your initiative, this is a money saving website and you, frankly, used this site last time with your questionaire to further your business venture.

So I wasn't surprised to see Martin(or his staff) delete all your posts.

Your difficulty is that you have set yourself an impossible task in trying to present a 'one size fits all' solution for an immensely complex subject.

Take solar PV, which is the simplest technology to predict output for any given area in UK.

Someone has posted a link on MSE for a calculator that does exactly what you intend. However you have to:

Fill in the cost of system(easy)
Give the predicted output(easily obtained if you know where to look)
Estimate future inflation rates over the next 25 years(impossible)
Estimate future fuel inflation rates over the next 25 years(impossible)
Estimate what saving/borrowing interest rates will be over the next 25 years(impossible)
Estimate what percentage of generated output you will use in property and what you will export(very difficult)
Estimate cost of repairs/maintenence over 25 years(impossible)

Provide you can answer all that lot it will give you some results; and that is for the easiest technology because the subsidies are known.

In any case, even if your calculator makes a decent fist of providing some figures, getting details of potential customers and delivering these details to firms who will pay you for that information, is hardly likely to be in those customer's interests. Just because a firm pays you, it is no guarantee they won't rip off the customers you send their way.

I suggest you need to contact Martin or his team if you want to use his website, but I suspect you will need to be able to convince him how your proposals will benefit his site and his readers.

RenwableSavings

Hi, thanks for your feedback.

I've taken on pretty much ALL of your points mentioned above re:calculator and added a non-logged in, instant Solar PV system search by postcode, price or KW size.

I think you will agree that it now brings value for MSE users and worth a mention.

Cheers, Trevor

keith_r59

As Cardew has pointed out, there are a number of calculators already out there which provide estimates for annual income and overall investment payback for Solar PV and yes the key word is estimate as no one can predict what will happen in the future. However, what they will show you is that the higher the inflation rate the quicker the payback time.

RenwableSavings

keith_r59 wrote: »

As Cardew has pointed out, there are a number of calculators already out there which provide estimates for annual income and overall investment payback for Solar PV and yes the key word is estimate as no one can predict what will happen in the future. However, what they will show you is that the higher the inflation rate the quicker the payback time.

Yes, that's why the calculator allows you to change many variable like that.

Also, the instant price search feature has had some great feedback from my current users. Try it and let me know what you guys think..?