Saturday, December 25, 2010

good idea in micro-scale photovoltaic energy systems

dec 25th, 2010

this sort of thing can be absolutely revolutionary.

RENEWABLE ENERGY. encouraging story on micro-scale energy systems. this is the future, not mega-corrupt projects.


Non Carborundum said...

There is no mention of the basic economics:

Capital cost per MW
Load Factor in %
Project Life in years
Assumed Annual O&M Cost
Therefore Cost of Generation per kWh

Such Decentralized Projects, including Biomass Projects set up in India by Husk Power Systems mentioned in the article, seem to me to be only about getting subsidies and cheating the local consumer who does not have access to grid power. The tariff works out to Rs. 14-15 / kWh even after subsidies and this has to be paid by poor villagers. The comparable domestic tariff slab for grid connected power is Rs. 3-4 / kWh. The Pachauri led TERI has also been propagating nonsensical Solar PV pilot projects in some states in India, notably West Bengal for several years now.

Photovoltaic technologies do hold promise with so many competing technologies in crystalline and thin film and since these are modular, can be deployed at the "micro" level. But Solar Thermal technology projects need to be of the order of 50 MW, and that is where true promise lies in my view. For Solar Thermal, Cost of Generation without subsidies is already touching Rs. 11 / kWh. In some time – maybe 5 years, Solar Thermal might be able to compete with Gas Based Thermal Power projects.

nizhal yoddha said...

non carborundum, there are large hidden costs to hydrocarbons and therefore to coal and gas-fired electric plants. for instance, the ports, the railroads, the pipelines: none of these is charged directly to the user of electricity. heck, as i have mentioned here before, even the cost of warships patrolling off somalia should be included in the fully-loaded cost of oil/gas/coal. but it isn't. to insist that a new technology like photovoltaic needs to fully amortize its capital cost vs. the hydrocarbon infrastructure which has been paid for with public money is not correct.

there is a classic paper by clayton christensen about 'the failure of leading firms' -- if you ignore a lower-end technology it may soon ride up the performance curve and then take over the market. good example is PCs vs. minicomputers. yes, it is true that in this case the new tech is more expensive, but that is only a scale issue. as PV esp thin film demand takes off, costs will crash.

unfortunately the chinese would have wiped out all the competing PV players by then, and will have a monopoly. already silicon valley PV players are retrenching, and china's share of PV has skyrocketed. india's share? about 0% as everybody runs after idiotic 'nucular'.

btw gujarat is offering a guaranteed rate for 10 years of rs 13/kwh for solar plants of 5 Mw or more. that seems to be sufficient for investors.

Non Carborundum said...


I generally agree. My problem is with these village level projects that have been done in India, most of which are pilot projects. These neither provide value nor the likelihood of any further technological innovation. The article mentions one "Husk Power Systems" that I know charges atrociously high amounts to villagers in Bihar for Biomass Generated Power in the absence of grid in certain villages. Then you have TERI that sets up these stupid solar lanterns, solar pump-sets (costing about Rs. 1.5 lakh) etc.

Under the first round of bidding under National Solar Mission, the lowest bid for Solar PV was Rs. 10.95 / kWh and for Solar Thermal was Rs. 10.49 / kWh. At these tariffs, now solar is moving pretty close in orders of magnitude to conventional cost of generation. Now it's about 3-4 times as costly as conventional power which is a remarkable achievement.

Under Solar PV, bidders had to quote for 5 MW projects and various forms of crystalline technology and thin film were offered by different developers. Under Solar Thermal, project size was allowed up to 100 MW as larger projects tend to have lower costs per MW and kWh.

Under both Solar PV and Thermal there are many different variants of technology. For instance, Solar Thermal has three main variants – parabolic trough, linear Fresnel and tower. Each of these can be done with or without storage (using molten salts). Further, the solar field which comprises of reflecting mirrors can be constructed using different materials like aluminium, or thin sheets of silver etc. Solar PV has much much more variants.

It is quite likely that with innovation and economies of scale in production costs could come down to conventional costs in say, 15 years.

I am personally more excited by Solar Thermal because it is not a very complicated technology, is currently cheaper on a per kWh basis, and is not dependent on assured supply of rare earth elements, 97% of which China controls.

nizhal yoddha said...

non carborundum, ok, i accept your point that pilot projects may not be sensible as they stand.

but i am more excited than you are about small scale PV systems because these can be sold first as simple inverter replacements. the price point of an inverter is about rs. 10,000 in india, so a comparable price level (say rs. 12,000 as there are no recurring electricity costs) for home PV systems may create good demand. heck, i can see a combo of hybrid cars with home PV systems charging them overnight based on good battery storage :-) this might appeal to the eco-conscious conspicuous consumer :-)

i agree also about photothermal. the one big success we have in india with solar is water heaters, which are sort of primitive photothermal systems -- simple, and pay for themselves fairly soon. but the problem with large solar thermal is land and water needed for it and then transmission lines needed to send it where it's needed.

Sita said...

I feel there is not much push in these micro-level projects because the govt. could not get much money out of it. I hope and pray,though, this kind of projects are available to the Indian Public.
Your blog and writing is very interesting and has raised many valid questions which is absent in our milieu,especially,now.
Bless You for speaking out. This is the first step to our nation"s regeneration.