Solar ... In the news

rogerblack

Martyn1981 wrote: »

It's interesting to read how they are doing this to prevent a public backlash against utility scale PV ....... despite there being no apparent backlash building up so far?

It occurs to me that there are a hell of a lot more people employed per watt for rooftop installs, so they're likely to have a proportionately higher amount of lobiests.

rogerblack

So, rooftop solar - residential - gets about 14p/kWh subsidy.
ROCs go for around 40 pounds, so 4p/kWh - and solar-rooftop gets 1.7ROCs/MWh.
Or, about 7p/kWh.

A bit silly that the residential segment gets the lions share of the total subsidy,
while providing around 40%.

And then there is the issue of inefficiencies in the domestic segment caused by substituting solar-PV for gas-thermal water heating, which eliminates carbon savings.

Martyn1981

rogerblack wrote: »

So, rooftop solar - residential - gets about 14p/kWh subsidy.
ROCs go for around 40 pounds, so 4p/kWh - and solar-rooftop gets 1.7ROCs/MWh.
Or, about 7p/kWh.

A bit silly that the residential segment gets the lions share of the total subsidy,
while providing around 40%.

And then there is the issue of inefficiencies in the domestic segment caused by substituting solar-PV for gas-thermal water heating, which eliminates carbon savings.

Aren't ROCs aimed at the supply side, hence why the ROC rate for roof mounted (1.6 ROCs) works out very similar to the FiT standalone rate of 6.38p?

For an equivalent (50kWp+) demand side roof mounted system under FiTs, the rate is 10.34p. [12.13p for 10-50kWp]

Personally I've always assumed that domestic FiTs was so generous so as to open it up to more properties, including off-south orientations, and northern England & Scotland, and to encourage/support the industry.

Strip these out, and aim only for south facing, southern England, and a FiT rate of 7p would almost work today. Let's say 4kWp, 4,000kWh generation, £5.5k cost, with £500 to £550 income pa. But the smaller market and lower levels of installs might not have brought about the cost reductions ...... so swings and roundabouts I suppose.

Mart.

EricMears

rogerblack wrote: »

And then there is the issue of inefficiencies in the domestic segment caused by substituting solar-PV for gas-thermal water heating, which eliminates carbon savings.

That's not really an 'issue'.


Electrical water heating would use carbon - IF it was using power ex grid. But if you only divert solar power to an immersion heater that won't consume any carbon at all.

Martyn1981

This article is more about oil, but raises some interesting points about future trends and PV specifically:

Oil industry on borrowed time as switch to gas and solar accelerates

Citigroup said solar already competes in the growing regions of the world on "pure economics" without subsidies. It has reached grid parity with residential electricity prices in Germany, Italy, Spain, Portugal, Australia and the US southwest. Japan will cross this year, Korea in 2018. It forecast that even Britain will achieve grid parity by 2020, a remarkable thought for this wet isle at 51 or 52 degrees latitude.

The industry can at last tap a "large investor universe" through the market for asset-backed securities. It priced debt below 5pc last year. Some US electric companies are starting to build solar farms for hard-headed commercial reasons as a hedge against future shifts in the gas price. This is astonishing.

Roughly 29pc of all electricity capacity added in America last year came from solar. The story is by now well-known. A McKinsey study found that installed solar power in the US across all sectors has dropped from $6 a watt to $2.59 in four years, largely due to the collapse in the cost of solar cells.
The next leap in competitiveness will come from falling "soft costs", currently 64pc of the residential solar price in America. This happened in Germany as scale built up, and is following in the US. In California you can sign up for solar panels in a supermarket, with no money down, and make a saving from day one.

The clinching shift will come when the battery storage is cheap enough and lasts long enough for users to draw down their suplus generated during the day to cover needs at night, opening the way for mass exodus from the grid, unless utilities harness it first to their own advantage.

Mart.

rogerblack

EricMears wrote: »

Electrical water heating would use carbon - IF it was using power ex grid. But if you only divert solar power to an immersion heater that won't consume any carbon at all.

Well - yes - sort of.
But FITs are not paid as we like solar panels. They're paid to reduce national carbon output.

If solar-PV was done on a net metering basis - with the generator just getting credits for their electricity usage, then there is no issue substituting.

1kWh of solar-PV used to replace gas heating reduces local carbon emissions - but the fact that electricity has not been exported to the grid means you need to cost that kWhs carbon emission at the average grid rate.

It's not been a net saving of carbon, but a small net gain - but is incentivised to the consumer as if it's a saving.

Martyn1981

Big power out, solar in: UBS urges investors to join renewables revolution

Big power stations in Europe could be redundant within 10-20 years as electric cars, cheaper batteries and new solar technologies transform the way electricity is generated, stored and distributed, say analysts at the world’s largest private bank.

In a briefing paper sent to clients and investors this week, the Zurich-based UBS bank argues that large-scale, centralised power stations will soon become extinct because they are too big and inflexible, and are “not relevant” for future electricity generation. Instead, the authors expect it to be cheaper and more efficient for households and businesses to generate their own energy to power their cars and to store any surplus energy in their own buildings even without subsidies.

In language more closely associated with green NGOs, the bank with assets of more than $1.5tn says it expects a paradigm shift away from large-scale conventional power plants. “Power is no longer something that is exclusively produced by huge, centralised units owned by large utilities. By 2025, everybody will be able to produce and store power. And it will be green and cost competitive, ie, not more expensive or even cheaper than buying power from utilities,” say the authors, who urge their financial clients to “join the revolution.”

“Solar is at the edge of being a competitive power generation technology. The biggest drawback has been its intermittency. This is where batteries and electric vehicles (EVs) come into play. Battery costs have declined rapidly, and we expect a further decline of more than 50% by 2020. By then, a mass [produced] electric vehicle will have almost the same price as a combustion engine car. But it will save up to €2,000 (£1,600) a year on fuel cost, hence, it will begin to pay off almost immediately without any meaningful upfront ‘investment’. This is why we expect a rapidly growing penetration with EVs, in particular in countries with high fossil fuel prices.”

“Electric vehicles are the key catalyst for driving mass adoption of battery storage technologies, as autos will fast-track mass production, which will be significant in driving down costs. We see battery costs moving down from $360/kWh today to $200/kWh by 2020, and as low as $100/kWh within 10 years. We believe that by 2020, lithium battery pack cost will drop by more than 50%, compared to 2013.

Mart.

ed110220

rogerblack wrote: »

Well - yes - sort of.
But FITs are not paid as we like solar panels. They're paid to reduce national carbon output.

If solar-PV was done on a net metering basis - with the generator just getting credits for their electricity usage, then there is no issue substituting.

1kWh of solar-PV used to replace gas heating reduces local carbon emissions - but the fact that electricity has not been exported to the grid means you need to cost that kWhs carbon emission at the average grid rate.

It's not been a net saving of carbon, but a small net gain - but is incentivised to the consumer as if it's a saving.

Burning fossil fuels in power stations to boil water to make steam to turn turbines and then transforming the voltage up to transmit the power across the country before transforming it down and distributing it is actually a pretty inefficient process.

If you burn one kWh of gas at home for heating, it produces 170 g of carbon dioxide. As boilers are not 100% efficient as not all the heat from combustion goes into heating the water the figure for 1 kWh of useful gas heating is about 190 g of CO2. If you use 1 kWh of electricity from the grid in the UK it produces on average 470 g of CO2.

So clearly using solar PV electricity instead of grid electricity saves much more carbon dioxide than using it to substitute for gas... Ie it's much better for the environment if not your pocket to export your spare generation for others to use than it is to use it instead of gas heating.

Ed

rogerblack

ed110220 wrote: »

If you burn one kWh of gas at home for heating, it produces 170 g of carbon dioxide. As boilers are not 100% efficient as not all the heat from combustion goes into heating the water the figure for 1 kWh of useful gas heating is about 190 g of CO2. If you use 1 kWh of electricity from the grid in the UK it produces on average 470 g of CO2.

So clearly using solar PV electricity instead of grid electricity saves much more carbon dioxide than using it to substitute for gas... Ie it's much better for the environment if not your pocket to export your spare generation for others to use than it is to use it instead of gas heating.

Sorry if I was unclear - this was the exact point I was trying to make.
The problem is this is not reflected in the incentives.
People are incentivised to swap gas for electricity.

ed110220

rogerblack wrote: »

Sorry if I was unclear - this was the exact point I was trying to make.
The problem is this is not reflected in the incentives.
People are incentivised to swap gas for electricity.

Hi, sorry I didn't mean to sound like I was criticising you, just wanted to give some numbers!

Ed