Green Spark Solar Blog

Solar Power

<h2>What is the cost of solar power in NZ in 2020?</h2><p>During the last decade, the price of solar power has plummeted in NZ. In 2009, a 3kw system was around $40k installed including GST, and in 2020 it would be more like $9,500. For most families, solar became a cheaper source of power than grid energy in about 2011. <br/></p><p>At the same time, there have been significant technical improvements both in solar panel and inverter design. So panels these days last longer, have better efficiencies and warranties and the same goes for inverters too. <br/></p><p>Pricing is a complicated matter and it always needs a site visit and discussion with clients to do it professionally. <br/></p><p>There are many different sizes of solar system, ranging from 2kw up to 10kw or more, but always in proportion to power consumption. There are quite a few criteria to take into account when giving a quote, and one quote is not the same as any other; but to give some rough idea of grid tied systems with price ranges, have a look at the following: <br/></p><p>2kw: $7,800- $9,700</p><p>3kw: $9,300- $11,500</p><p>5kw : $13,200 - $15,700</p><p>10kw: $23,400 - $26,600<br/></p><p>To make some judgements on what is best money for value; firstly there is the quality of the equipment itself. Top of the range double glass panels from a reputable manufacturer are a higher quality than cheaper plastic backed panels with a no name brand even if the wattage is the same. <br/></p><p>There are also differences in the way these panels act in various conditions. So for example, if they have PERC technology or not could be a really big thing in dark winter weather or early morings and evenings, perhaps up to 30% difference. Another factor is if they are using split cell technology or not, as the number of connections within the panel has a bearing on how efficient it will be. <br/></p><p>Then, there are the questions about what happens if the panel is put under stress like from a freakish hail storm, fire, earthquake or heavy snow load. <br/></p><p>Then of course, there is the maintenance. Anything with a frame is going to have to cleaned much more frequently. <br/></p><p>Regarding inverters, warranty is everything and the warranty is only as good as the track record of the manufacturer honoring warranties. Generally German or Australian warranties are considered highly reliable. Whether the inverter is three phase or single phase is likely going to be a price difference of up to $1500.<br/></p><p>The installation can have a big bearing on  price. Scaffolding costs a fortune but is necessary for steep roofs and double story houses. Next, if you have tiles, coloursteel, decro or membrane roofing will impact the type of fixings to use and and how quickly the work can be done. <br/></p><p>If there is some distance between panels and distribution board then this might mean conduit either internal or external, maybe with some wall drilling. If there is not a lot of ceiling space then iron may have to pulled up to get cables underneat. <br/></p><p>Speed of install is only good when it is done accurately and installation teams vary a lot in how long they take and how accurate they are up to a factor or 2 or 3 times. Some solar companies pay their installers little, encouraging them to rush and cut a few corners. Generally if the price looks too low and out of range of what is described above, then something might not be right. <br/></p><p>Another aspect is travel if the site is in a far off location…<br/></p><p>So, above are solar quotes for grid tied systems. If you want a battery then that is called a hybrid and that will cost a lot more. You will need a more elaborate hybrid inverter and then battery storage and then more panels to charge the batteries in winter. There are small battery systems around but they are rarely adequate, realistically 10-14kw of storage is where to begin and all up this could add about $15k to grid tied pricing. <br/></p><p>Off grid solar costing is much more involved. A generator backup is compulsory. For about $19,500 you can get something that will power a batch and run a fridge, lights, kitchen equipment and a TV. There are cheaper caravan based versions of these around and they never work right. Ask your solar assessor to do a power audit and you will soon see why. Big off grids for large houses can be anyhing from $55-$100k; again this is very customised work. <br/></p><p>To get a clear quote for solar for your own home please contact <b><a href="https://greensparksolar.co.nz/contact.php">Green Spark Solar.</a></b><br/></p>

What is the cost of solar power in NZ in 2020?

During the last decade, the price of solar power has plummeted in NZ. In 2009, a 3kw system was around $40k installed including GST, and in 2020 it would be more like $9,500. For most families, solar became a cheaper source of power than grid energy in about 2011.

At the same time, there have been significant technical improvements both in solar panel and inverter design. So panels these days last longer, have better efficiencies and warranties and the same goes for inverters too.

Pricing is a complicated matter and it always needs a site visit and discussion with clients to do it professionally.

There are many different sizes of solar system, ranging from 2kw up to 10kw or more, but always in proportion to power consumption. There are quite a few criteria to take into account when giving a quote, and one quote is not the same as any other; but to give some rough idea of grid tied systems with price ranges, have a look at the following:

2kw: $7,800- $9,700

3kw: $9,300- $11,500

5kw : $13,200 - $15,700

10kw: $23,400 - $26,600

To make some judgements on what is best money for value; firstly there is the quality of the equipment itself. Top of the range double glass panels from a reputable manufacturer are a higher quality than cheaper plastic backed panels with a no name brand even if the wattage is the same.

There are also differences in the way these panels act in various conditions. So for example, if they have PERC technology or not could be a really big thing in dark winter weather or early morings and evenings, perhaps up to 30% difference. Another factor is if they are using split cell technology or not, as the number of connections within the panel has a bearing on how efficient it will be.

Then, there are the questions about what happens if the panel is put under stress like from a freakish hail storm, fire, earthquake or heavy snow load.

Then of course, there is the maintenance. Anything with a frame is going to have to cleaned much more frequently.

Regarding inverters, warranty is everything and the warranty is only as good as the track record of the manufacturer honoring warranties. Generally German or Australian warranties are considered highly reliable. Whether the inverter is three phase or single phase is likely going to be a price difference of up to $1500.

The installation can have a big bearing on  price. Scaffolding costs a fortune but is necessary for steep roofs and double story houses. Next, if you have tiles, coloursteel, decro or membrane roofing will impact the type of fixings to use and and how quickly the work can be done.

If there is some distance between panels and distribution board then this might mean conduit either internal or external, maybe with some wall drilling. If there is not a lot of ceiling space then iron may have to pulled up to get cables underneat.

Speed of install is only good when it is done accurately and installation teams vary a lot in how long they take and how accurate they are up to a factor or 2 or 3 times. Some solar companies pay their installers little, encouraging them to rush and cut a few corners. Generally if the price looks too low and out of range of what is described above, then something might not be right.

Another aspect is travel if the site is in a far off location…

So, above are solar quotes for grid tied systems. If you want a battery then that is called a hybrid and that will cost a lot more. You will need a more elaborate hybrid inverter and then battery storage and then more panels to charge the batteries in winter. There are small battery systems around but they are rarely adequate, realistically 10-14kw of storage is where to begin and all up this could add about $15k to grid tied pricing.

Off grid solar costing is much more involved. A generator backup is compulsory. For about $19,500 you can get something that will power a batch and run a fridge, lights, kitchen equipment and a TV. There are cheaper caravan based versions of these around and they never work right. Ask your solar assessor to do a power audit and you will soon see why. Big off grids for large houses can be anyhing from $55-$100k; again this is very customised work.

To get a clear quote for solar for your own home please contact Green Spark Solar.

Posted 9 weeks ago
<p>Good time to shut down Huntly Power Station, replace with solar</p><p>Huntly Power Station is on its way out. The combination coal/gas fired plant is being wound down, with plans to decommission two of the coal/gas generators by 2022, and by 2025 to only be using coal in abnormal conditions; and by 2030 to not be using this facility at all. <br/></p><p>Huntly is the single largest greenhouse gas emitter in NZ. Half of all greenhouse gases from power generation just originate from here. Huntly has been the focus of sustained environmental protests since 2007. The main reason it is still in existence is because Geneis uses it in times when dam storage is low and hydro power is compromised. <br/></p><p>Huntly’s peak output is 1 GW.</p><p>If the electrical infrastructure was kept in place, but a 1 GW solar power station was built around Huntly, then this would be a mega project that would keep around 10,000 people directly employed for at least a year, which is exactly what need right now. Some 30 square kilometers would be needed to mount the panels, land that Huntly does not possess, but there are two nearby water reservoirs that do have this surface area, and some  3 million solar panels could be floated there on pontoon type structures. The added benefit being that these pontoons prevent water evaporation while cooling the panels and increasing their efficiency. <br/></p><p> A project like this is worth about $1.5 Billion which sounds like a lot, but the government is borrowing money at 1.5% interest and the return from a plant like this might be around  7%. So this could be a profit making venture that generates additional revenue above borrowing costs from the  very first month.</p><p>Considering this money will have to spent sooner or later as Huntly goes, why not just speed up the process. . <br/></p><p>As New Zealand moves to renewables like large solar power plants it will need power storage to regulate the grid. Pumped hydro could be a good solution because the dam infrastructure is already there and some regions are having problems with droughts and low dam levels. Water could be pumped there during peak solar production times then released in the evenings during times of peak demand. The additional water having added benefits for irrigation and drinking supply. <br/></p>

Good time to shut down Huntly Power Station, replace with solar

Huntly Power Station is on its way out. The combination coal/gas fired plant is being wound down, with plans to decommission two of the coal/gas generators by 2022, and by 2025 to only be using coal in abnormal conditions; and by 2030 to not be using this facility at all.

Huntly is the single largest greenhouse gas emitter in NZ. Half of all greenhouse gases from power generation just originate from here. Huntly has been the focus of sustained environmental protests since 2007. The main reason it is still in existence is because Geneis uses it in times when dam storage is low and hydro power is compromised.

Huntly’s peak output is 1 GW.

If the electrical infrastructure was kept in place, but a 1 GW solar power station was built around Huntly, then this would be a mega project that would keep around 10,000 people directly employed for at least a year, which is exactly what need right now. Some 30 square kilometers would be needed to mount the panels, land that Huntly does not possess, but there are two nearby water reservoirs that do have this surface area, and some  3 million solar panels could be floated there on pontoon type structures. The added benefit being that these pontoons prevent water evaporation while cooling the panels and increasing their efficiency.

 A project like this is worth about $1.5 Billion which sounds like a lot, but the government is borrowing money at 1.5% interest and the return from a plant like this might be around  7%. So this could be a profit making venture that generates additional revenue above borrowing costs from the  very first month.

Considering this money will have to spent sooner or later as Huntly goes, why not just speed up the process. .

As New Zealand moves to renewables like large solar power plants it will need power storage to regulate the grid. Pumped hydro could be a good solution because the dam infrastructure is already there and some regions are having problems with droughts and low dam levels. Water could be pumped there during peak solar production times then released in the evenings during times of peak demand. The additional water having added benefits for irrigation and drinking supply.

Posted 11 weeks ago
<p><b>Growth of Solar Hybrid Systems during a crisis<br/></b></p><p>As soon as the lockdown hit across the world, entire families stayed at home all day, some working and everyone using power. For most people, they have found their power bills to go up about double the normal amount and this effect will be exaggerated as winter comes on and electrical heating systems are running all day. <br/></p><p>We have also seen disruptions to the phone networks and internet services due to demand. Although industrial areas are not using power, residential areas are using a lot more and when winter comes it is quite conceivable that blackouts will be common. <br/></p><p>Another danger is if a critical number of engineers that run the national grid all get sick together - these are specialist skills that only a few people have and those technicians are not easily replaceable. The entire grid might have to be ramped down if that happens.<br/></p><p>Fortunately there is a solution - power your own home with solar and store it in a battery while maintaining connection to the grid. This is called a hybrid power system. If there is a general blackout, then you will be independent and your food supplies secure. All the meat you have been hoarding will stay frozen and you will still have lights and emergency heating. <br/></p><p>If your battery is full and the solar system is generating more power than you need during the day then that excess power is sent back to the grid and this provides a wider social benefit - you are providing available power to your neighbours and lessening the chance of a general blackout. <br/></p><p>Hybrid systems can be financed in an easy way with no money upfront and the power savings essentially paying for any repayment with a clear financial benefit that customers can realise from month one. <br/></p>

Growth of Solar Hybrid Systems during a crisis

As soon as the lockdown hit across the world, entire families stayed at home all day, some working and everyone using power. For most people, they have found their power bills to go up about double the normal amount and this effect will be exaggerated as winter comes on and electrical heating systems are running all day.

We have also seen disruptions to the phone networks and internet services due to demand. Although industrial areas are not using power, residential areas are using a lot more and when winter comes it is quite conceivable that blackouts will be common.

Another danger is if a critical number of engineers that run the national grid all get sick together - these are specialist skills that only a few people have and those technicians are not easily replaceable. The entire grid might have to be ramped down if that happens.

Fortunately there is a solution - power your own home with solar and store it in a battery while maintaining connection to the grid. This is called a hybrid power system. If there is a general blackout, then you will be independent and your food supplies secure. All the meat you have been hoarding will stay frozen and you will still have lights and emergency heating.

If your battery is full and the solar system is generating more power than you need during the day then that excess power is sent back to the grid and this provides a wider social benefit - you are providing available power to your neighbours and lessening the chance of a general blackout.

Hybrid systems can be financed in an easy way with no money upfront and the power savings essentially paying for any repayment with a clear financial benefit that customers can realise from month one.

Posted 13 weeks ago
<p>Christchurch Hospital gets Solar Power!</p><p>Recently a 45kw industrial solar system was commissioned at the Christchurch Eye Hospital. Power supply had long been an issue at this site, and it was beginning to affect hospital services, especially air conditioning in operating theaters which is quite important for delicate work. <br/></p><p>45kw is a lot of power and the system had to be engineered in such a way that power exports on weekends were automatically controlled to be kept under set limits, while maximising production during peak weekdays. <br/></p><p>The system used top of the line SMA German designed equipment and double glass panels for their durability and low maintenance and exceptional long warranties. <br/></p><p>The timing was good in that the hospital is now equipped for Covid-19 power demands - extra beds and ventilators can now be catered for without the risk of blowing a fuse. <br/></p>

Christchurch Hospital gets Solar Power!

Recently a 45kw industrial solar system was commissioned at the Christchurch Eye Hospital. Power supply had long been an issue at this site, and it was beginning to affect hospital services, especially air conditioning in operating theaters which is quite important for delicate work.

45kw is a lot of power and the system had to be engineered in such a way that power exports on weekends were automatically controlled to be kept under set limits, while maximising production during peak weekdays.

The system used top of the line SMA German designed equipment and double glass panels for their durability and low maintenance and exceptional long warranties.

The timing was good in that the hospital is now equipped for Covid-19 power demands - extra beds and ventilators can now be catered for without the risk of blowing a fuse.

Posted 13 weeks ago
<p>Solar Power in the Age of Covid-19</p><p>The Global Lockdown has ceased solar installations around the world 
for the time being. Until a vaacine is developed, future work on homes 
is likely to be severely curtailed. But, like many countries NZ is 
planning a massive public infrastructure spend to try and kick start the
 economy and prevent too many businesses going under. <br/></p><p>Solar 
is in an ideal position to benefit from this spend for several reasons. 
The first is that solar actually saves money over time, and because the 
financial return in the form of power savings from solar can be reliably
 calculated, then this return can effectively pay for the infrastructure
 if the government were to finance wide scale solar projects with a long
 enough payment period. After a few years those investments and interest
 would be paid for by solar savings and then there would be decades 
where government actually gets a net financial return far in excess of 
its initial investment . In fact no investment might be required all 
beyond establishing a formal repayment plan to bank lenders.</p><p>Solar
 power is a labour intensive activity that employs a lot of people for a
 period of time - electricians, labourers, project managers and 
engineers. There are also supporting contractors like earthworks, 
freight companies, equipment suppliers and even accomodation and food if
 work is done in remote areas.</p><p>An example of a quick moving 
project that could be implemented in a few weeks from now would be to 
retrofit solar on all the 220 hospitals in NZ. Some of the smaller 
regional hospitals may be in need of additional power security because 
if they become filled with hospital beds and ventilators they may exceed
 their own ability to deliver emergency care. Hospitals do have back up 
generators but these are not infallible and have been known to fail from
 time to time and are dependent on imported fuel supplies remaining 
stable. That is a very obvious short term benefit, but long term 
sustainability plans like impletmenting solar were on the books anyway 
for many hospitals.</p><p>A project like this could be underway in a fortnight. Areas of particularly low employment could be targeted first. <br/></p><p>A
 bigger project involving many hundreds of people over a year or more 
would be to build a solar power plant on a multi-megawatt scale. Such a 
project should be located near existing industrial transformers such as a
 hydroelectric plant, wind farm or coal burning generator. There would 
have to be considerable planning and coordination, but it would be a 
good mid term way to employ a lot of people installing useful 
infrastructure.</p><p>A key issue with these projects is how the workers
 prevent exposure to Covid-19 and what happens if an outbreak occurs in a
 crew? Fortunately much of the work is outdoors on rooftops or open 
fields and close contact is not a requirement. If a crew did get an 
outbreak, they would have to be isolated and replaced quickly with 
another healthy crew, and not infecting the entire solar work force. 
Possibly these crews would have to create their own work bubbles - maybe
 comandeering a hotel just for them for example. </p>

Solar Power in the Age of Covid-19

The Global Lockdown has ceased solar installations around the world for the time being. Until a vaacine is developed, future work on homes is likely to be severely curtailed. But, like many countries NZ is planning a massive public infrastructure spend to try and kick start the economy and prevent too many businesses going under.

Solar is in an ideal position to benefit from this spend for several reasons. The first is that solar actually saves money over time, and because the financial return in the form of power savings from solar can be reliably calculated, then this return can effectively pay for the infrastructure if the government were to finance wide scale solar projects with a long enough payment period. After a few years those investments and interest would be paid for by solar savings and then there would be decades where government actually gets a net financial return far in excess of its initial investment . In fact no investment might be required all beyond establishing a formal repayment plan to bank lenders.

Solar power is a labour intensive activity that employs a lot of people for a period of time - electricians, labourers, project managers and engineers. There are also supporting contractors like earthworks, freight companies, equipment suppliers and even accomodation and food if work is done in remote areas.

An example of a quick moving project that could be implemented in a few weeks from now would be to retrofit solar on all the 220 hospitals in NZ. Some of the smaller regional hospitals may be in need of additional power security because if they become filled with hospital beds and ventilators they may exceed their own ability to deliver emergency care. Hospitals do have back up generators but these are not infallible and have been known to fail from time to time and are dependent on imported fuel supplies remaining stable. That is a very obvious short term benefit, but long term sustainability plans like impletmenting solar were on the books anyway for many hospitals.

A project like this could be underway in a fortnight. Areas of particularly low employment could be targeted first.

A bigger project involving many hundreds of people over a year or more would be to build a solar power plant on a multi-megawatt scale. Such a project should be located near existing industrial transformers such as a hydroelectric plant, wind farm or coal burning generator. There would have to be considerable planning and coordination, but it would be a good mid term way to employ a lot of people installing useful infrastructure.

A key issue with these projects is how the workers prevent exposure to Covid-19 and what happens if an outbreak occurs in a crew? Fortunately much of the work is outdoors on rooftops or open fields and close contact is not a requirement. If a crew did get an outbreak, they would have to be isolated and replaced quickly with another healthy crew, and not infecting the entire solar work force. Possibly these crews would have to create their own work bubbles - maybe comandeering a hotel just for them for example.

Posted 13 weeks ago

Off Grid Solar for Maori Community

Traditional Maori lands in NZ are a prime candidate for solar power. This is not only because many are in remote areas and do not have regular access to mains electricity; but also because there is a strong feeling of ancestral connection to the land, and that it should be cared for in a respectful, non polluting way.

Near the Okutu Marae, (meeting place) Akaroa, Green Spark Solar recently installed a small off grid solution for a batch that previously relied on a generator that was costing $400 per month in fuel. Our well experienced team was able to fully install the easy to use system in one day. Because of limited roof space we used 300w panels with the latest nanocarbon batteries and our own Integrated Inverter System.

Posted 139 weeks ago

Large off grid solar project goes live in Twizel, NZ.

In an isolated forest close to Lake Pukaki there is a large log house. Up to to this stage the owners had to rely on a 12 kva diesel generator that was loud and polluting and required a lot of maintenance and diesel fuel.

To get mains power to the site would require a cable kilometres long at an expense of some $120,000. Green Spark Solar was invited to give an assessment and was able to take the lodge fully off grid using 10.6kw of solar panels with German built SMA inverters and Nanocarbon batteries; for a fraction of this price. 

The installation was typically challenging. The soil was glacial morraine and had large boulders immediately under the surface. Some of the heaviest rains in living memory took place during the installation. The permafost melted, the roads dissolved and a considerable amount of time was spent just keeping the site accessable.

Steel beams were set deep in the earth to mount the array; about double the normal amount due to high wind speeds, earthquakes and snow loads.

Posted 142 weeks ago

Canterbury Mountaineering Club (CMC) installs solar off grid system.

image

The CMC flagship hut, Wyn Irwin, is located in the Mt Cook national park far from any power source. This particular area is prone to cyclone strength winds which in the past have physically ripped the entire roof off and blown it more than a mile across the mountains. Winter temperatures can also be severe, getting down to minus 25 on occasion.

The hut is an important base for mountaineers exploring the region and Green Spark Solar won the tender to deliver the strongest off grid solar installation ever done in NZ.

On the club’s board are two of the most senior engineers in NZ, one structural the other electrical who scrutinised every detail down to physical principles. Engineering requirements were so tough that the entire structure of the building first had to be strengthened with extra beams, rafters and purlins. Solar panels were of the toughest double glass construction. About six times as many fixings were used as normal to keep the panels on the roof and a triple railing system with silicon pads was erected under the panels to give extra insurance from heavy snow loads and wind blasts.

Wyn Irwin is in a natural alpine valley with steep rock walls and limited sunlight hours. Panels had to be efficient enough to generate enough power in a small time window. The club elected to use German designed SMA inverters, and the best nanocarbon batteries with around 3 or 4 times the performance of normal lead acid cells.

Hardy volunteers from the club helped technical experts from Green Spark Solar complete the whole installation and rewire the lodge in about 4 days, partly during a blizzard.

As a back up the club installed a Kubota diesel generator, in practice this has not been used much beyond keeping itself in working condition. Climbers can now enjoy a fridge, toaster, electric kettle, lights, heating and even a washing machine; as well as charging up GPS’s, radios and avalanche beacons - increasing their comfort and safety using renewable energy.

image
Posted 143 weeks ago

The Accuracy of the EECA Energywise Solar Calculator is Questionable

In late 2016, the New Zealand Energy Efficiency and Conservation Authority (EECA) produced and marketed a solar calculator, claimed by them to assist homeowners in making decisions about solar power.

The calculator was heavily promoted and advertised, both on TV, Facebook, Google Adwords and print media.

Unfortunately there are some strange inacuracies built into this device – it gives misleading results, and according to the NZ Green Party, it attracted a deluge of complaints as soon as it was launched.

Many of these complaints and criticisms ended up in a steady stream on the Facebook page for EECA Energywise. Just as steadily, EECA mysteriously deleted these comments.

In terms of power production in kW per annum it is actually reasonably accurate. The calculator relies on NIWA data and it matches what solar installers know about their customer results. From that point there is a major divergence.

The basic problem is that the calculator acknowledges zero storage during the day, when in fact almost all Kiwis already have plenty of storage, in the form of hot water tanks, underfloor heating, night stores, spa pools, swimming pools and deep freezers. All of these devices can be run on timer systems so that they activate during the day using free solar energy, and turn off at night. Washing machines and dishwashers can be used selectively for day time only use for a similar results.

Using LED lights with solar is as common as icing on cakes to reduce night time lighting costs, also noticeable by its absence.

When I asked the calculator’s inventor, Dr. Alan Wood why these important factors were not included in the calculator. He said “It is true that energy storage and customer behavioural change are not modelled….it is extremely difficult to include the effect of these extra behaviours”.

I asked him if he would agree that any calculator not including storage would give a vastly distorted result 10 years or more out of sync with reality – I never got a reply.

I ran a quick scenario with an average power bill and the calculator gave me a result of about 18 years to break even, a result I believe to be nonsense because of the number of customers with the same bill we personally know that get a much superior outcome. My colleagues and I repeatedly asked EECA to provide examples of real people that are getting results matching their calculator. Not only did they never reply, but they deleted our persistent questions from their Facebook page.

There are some other assumptions within the calculator that look a bit dubious. One of these is the predicted future price of power being at 1.5% (about the same as the CPI). However, historically power has been increasing in price at a much higher rate – about 5.85% from 2003-2012 according to the MBIE. Future demand for electricity is also likely to be heavily influenced by the rise of electrical vehicles. All the energy coming directly from petrol and diesel will have to be supplied by electrical generation. This is not acknowledged in the above estimates.

With the cost of power rising rapidly, the relative savings of a solar system also increase rapidly. In fact, the relative savings increase at a faster rate than any degradation

The calculator also assumes that a solar system lasts for 25 years. Dr. Wood is confusing warranty periods with system life. So at 25 years, the system will still be operating at 80% efficiency and extra panels could be added at that stage to bring it up to a higher level, it is only the warranty that would expire. Because the level of panel degradation (0.5% on Duomax panels) is less than the rate of power price increases, in 25 years it will actually be saving more money than in year 1, not less.

There is a Net Present Value NPV section included in the calculator that compares the return on investment compared to another investment (money left in the bank). There are several problems with this approach:

-         It doesn’t acknowledge that a solar pv system adds value to a house as soon as it is put on. A solar powered house is easier to sell and commands a higher price.

-         Whatever savings are generated from the solar system are tax free. But bank account earnings are taxed.

-         Solar systems have warranties covering their output performance (effectively a guarantee, which banks do not have).

-         Solar savings are normally left to accumulate in a bank account, generating compound interest over time. For most clients, this ends up being about 10 times the financial benefit if they had left the money in the bank instead of investing in solar.

-         The choice is not between paying for solar or having no power cost at all. This is because if a client didn’t have solar they would still have to pay for power from the grid (at a higher rate). Either way, the money gets spent anyway – the real choice if a client wants an investment or not. It’s a bit like the difference between mortgage (ownership) and rent.


So why is EECA doing this? Dr. Wood says that he is receiving no financial advantage at all and I have no reason to disbelieve him. But you look at the bottom of the calculator in the disclaimer section it mentions that  Transpower is partially funding his research program.

Transpower owns and operates the nationwide grid in New Zealand. In some circles it is thought that solar power presents a great challenge to the viability of the national grid, because as more people use solar the less they need Transpower’s services and the less economic these services become.  On its own website it states that

“Transpower has a major investment programme to address:

-         Strong recent growth in electricity demand and predicted growth over the next 40 years.

-         The need to connect a diverse range of new sources of generation.

-         The ageing of the grid”

Posted 171 weeks ago

Energy Disaster in South Australia opens golden opportunity.

South Australia’s energy grid has taken a battering recently. Firstly there were   a series of terrific storms over a few months, with enough force to physically blow down several pylons. Then there was a period lasting more than a month with soaring temperatures more than 40 degrees every day. Black outs ensued - the grid was not able to cope and millions of people got roasted in the dark.

Part of the problem is the privatisation of the power industry in Australia - essentially if it had been centralised then other backups could have been implemented quickly.

South Australia did away with coal fired plants forever in 2016, with a large portion of is generation being taken up by wind (43%) and solar. Unfairly, these technologies were blamed for the outage, when in fact it was largely a physical problem with the lines themselves (they fell over).

Elon Musk came up with an audacious plan to deliver 100-300 Megawatts of centralised battery storage, to be installed in 100 days. Sounds crazy, but no worse than building your own rockets to Mars. History suggests he can probably pull it off. This would be a new thing,to install  a battery bank large enough to stabilise a whole state and it could shake up global expectations of what is practical and achievable in this area.

Centralised battery storage is the most obvious way for power utilities around the world to stay relevant as the solar revolution gathers pace. As I wrote in an earlier post,  tiny Alpine Energy in Timaru actually already does this on a more modest scale. Daytime generation is stored in a room sized Lithium battery and released at peak evening times.

It looks like the SA state government is going to go ahead with Musk or another battery provider, but rather than take the bold step of using more and newer solar systems to provide power generation, they decided to implement a yesteryear gas fired plant. It’s a bit like going back to using analog phones or black and white television; but the power instability is doing wonders for the domestic solar industry over there, where ordinary citizens can own their own power plant and battery bank and be fully independent if there are future blackouts.

Posted 172 weeks ago