Category Archives: CSIR

Renewables-heavy mix is South Africa’s cheapest option, yet another study confirms

Engineering News, 1 December, 2017

A new, independently produced techno-economic model of South Africa’s cost-optimal power generation mix in 2040 outlines a system where 69% of the electrical energy is produced from onshore wind and solar photovoltaic (PV) generators, supported by batteries and gas-fired generators.

Conducted by the Frankfurt Institute for Advanced Studies (FIAS), the study concludes that there will be no need for the addition of new coal or nuclear power stations beyond what is already installed.

The DoE document makes pricing assumptions for various generation technologies and assumes, optimistically, that total yearly electricity demand will grow to 428 TWh by 2040, from around 250 TWh currently.

However, the study’s parameters deviate from the draft IRP by aligning wind and solar PV costs with the R0.62/kWh achieved during the most recent bid window of the Renewable Energy Independent Power Producer Procurement Programme.

‘Moderate’ learning rates have been assumed that halve the cost reductions forecasted by Bloomberg New Energy Finance. The analysis by FIAS assumes that, by 2040, the overnight costs for onshore wind will reduce by one-quarter and for solar PV by one-third, while energy storage costs will drop by half. However, Hörsch notes that even if the analysis were to be based on today’s costs, the results would not change qualitatively.

Another deviation is that the assumptions have been modelled using the PyPSA software tool, rather than the sophisticated Plexos system used by Eskom and the DoE to produce South Africa’s IRP. However, Hörsch stresses that the models are mathematically identical.

The outcome is a least-cost configuration in 2040 comprising 53% wind, 16% solar PV and 25% coal, with the balance of the energy derived from nuclear, gas, hydro and batteries.

The system will still comprise 19 GW of residual coal-fired generation and 1.8 GW of nuclear in the mix, despite the closure of several coal plants between 2020 and 2040. There will also be 2.9 GW of pumped storage, while Cahora Bassa is expected to contribute 1.5 GW of capacity.

Increasingly, though, the variable wind and solar generators will need to be backed up by 11 GW battery units and 12 GW closed cycle gas turbines.

The least-cost mix has an average system cost of R510/MWh in 2040; a “base case” that is nearly 20% cheaper than a scenario where at least 10 GW apiece of new coal and new nuclear is incorporated into mix.

Hörsch adds that the integration of renewables generators is also relatively cheap and easy, owing to the fact that the expansion of the South African transmission system is less land-constrained than is the case in many other countries, particularly those in Europe.

“Only a moderate expansion of transmission corridors will be needed, comprising only 10%, or R10/MWh, to the yearly system cost in 2040,” he explains.

The results are more or less in line with a recently updated techno-economic study conducted by the CSIR Energy Centre, which pointed to a least-cost electricity mix, by 2050, in which solar PV and onshore wind contribute nearly 80% of the country’s electrical energy.

However, the FIAS study has a higher proportion of wind compared with solar PV than is the case with the CSIR study, which outlines almost even contributions from the two renewables technologies.

Hörsch attributes this deviation in results to the fact that the PyPSA analysis forecasts greater “smoothing” in the variability associated with wind generation as a result of the geographical distances between generators assumed in the model.

Secondly, the FIAS study has included higher costs for battery energy storage than is the case in the most recent CSIR analysis, released in November. Lower battery costs would result in a higher penetration of solar PV, with batteries materially reducing the variability associated with the technology and extending operating hours into periods when the sun is no longer shining.

The latest CSIR study, also includes a moderate amount of battery electric vehicles and flexibility arising from demand side management, which favours a higher penetration of solar PV.

Both studies concur, though, that the cheapest future mix will be renewables-led and that the introduction of additional new coal and new nuclear will only raise overall system costs.

“Overall, our investigation shows that renewable energy in South Africa is incredibly cheap and easily integrated into the system,” Hörsch states, adding that the main conclusion is that South Africa should immediately turn its attention to building a future mix based on solar PV and wind. 

Here is the link to the article

Eskom’s latest work on the IRP for the DoE rejects nuclear

Engineering News, Chris Yelland, 24 November, 2017.

Nuclear doesn’t make sense, does it?

The findings of the latest work on the draft Integrated Resource Plan for Electricity, IRP 2017, by Eskom for the South African Department of Energy (DoE) are proving to be somewhat problematic for Energy Minister David Mahlobo.

As a result, this latest work by Eskom, and all further work on IRP 2017, has now been taken out of the hands of both Eskom and the DoE planning technocrats by Minister Mahlobo and his nuclear team so they can “massage” it further with “policy adjustment”.

The Eskom work confirms studies by other respected research bodies in South Africa and abroad, as well as the statements by Finance Minister Malusi Gigaba at the recent World Bank and International Monetary Fund summit in New York, and in his medium-term budget policy statement, that the new-nuclear option for South Africa is both unnecessary and costly.

After modelling numerous scenarios in the latest work by Eskom, the study focusses on five broad scenario options, referred to by Eskom as: the Reference Case; the Optimum Plan; the Low Growth Scenario; the Carbon Budget Plan; and the Forced Nuclear scenario.

In the Forced Nuclear scenario, some 9,6 GW of new-nuclear power is “hardwired” (or forced) into the IRP model in the years to 2050, because none of the other scenarios modelled come up with this particular outcome, which appears to be preferred by the DoE nuclear team and the Zuma administration.

For the first time, this latest work by Eskom incorporates the cost of transmission infrastructure, by including these costs for all the generation technologies and scenarios modelled. Eskom concludes that contrary to what is often heard, the total cost of grid integration of renewable energy, coal, gas or nuclear is actually minimal in comparison to the cost of the generation component.

Based on local and international studies, and real-world experience, and again contrary to what is often heard from nuclear evangelists (including those within Eskom itself), the latest Eskom study shows that the overnight capital cost of new nuclear in SA is the highest by far of all the generation technologies, significantly higher even than that of concentrating solar power (CSP) with nine hours of energy storage.

Specifically, the study finds that the overnight capital cost of new nuclear power in South Africa comes in at US $5141 per kW installed. This is compared to $680 per kW for OCGT, $747 for CCGT, $1390 per kW for wind, $1220 per kW for fixed-tilt solar PV, $4336 per kW for CSP with nine hours of energy storage, and from $2950 to $3560 per kW for new coal.

The Forced Nuclear scenario, in which 9,6 GW of nuclear new-build is “hardwired” into the IRP model, would increase the electricity price trajectory in South Africa significantly more than that for any of the other viable scenarios modelled, with prices approximately R0,15 per kWh higher than that of the Optimum Case.

The Eskom study goes further to show that from 2030 to 2050 the cumulative electricity cost to customers resulting from the R0,15 per kWh higher electricity price of the Forced Nuclear scenario is some R800-billion higher than that of the Optimum Plan scenario, and R500-billion higher than that of the Reference (Base) Case scenario.

In the Carbon Budget scenario modelled by Eskom, a median demand growth is assumed, and a more demanding approach to CO2 emission reduction is taken. In addition, solar PV and wind capacity is artificially (i.e. politically) constrained at 1 GW and 1,8 GW per annum respectively. This forces 5,6 GW of new nuclear power into the IRP (made up of  4 x 1,4 GW reactors), but these are only required in 2039, 2040, 2045 and 2046 respectively.

In the Optimum Plan scenario modelled by Eskom, where a median demand growth is assumed, together with the more moderate “peak-plateau-decline” approach to CO2 emission reduction, and with no annual caps on wind and solar PV, the study shows that no new nuclear power is required at all in the years to 2050.

In fact, even in the base case Reference Plan scenario, where the artificial annual constraints of 1 GW and 1,8 GW per annum are imposed for wind and solar PV, together with a median demand growth forecast and the “peak-plateau-decline” approach to CO2 emission reduction, no new nuclear is required by 2050 at all.

In response to this article, Eskom has indicated that it unable to comment as it is not aware of the contents of the IRP. “The Eskom team is only involved in terms of providing the modelling work, with the approach and inputs given by the Department of Energy”, said Eskom spokesman Khulu Phasiwe. The DoE did not respond when given the opportunity for right-of-reply.

In summary, the Eskom modelling work makes it clear that the unconstrained least-cost scenario of the Optimum Plan does not include any new nuclear power, regardless of demand projections and COlimits. Furthermore, the modelling shows that the only way to getting new nuclear into the IRP is by artificially constraining renewable energy, or by taking a hardwired “Forced Nuclear” approach.

Perhaps it is these realities highlighted in the latest modelling work and findings by Eskom that are giving the DoE planners and nuclear team some headaches, leading to the delay in the release of IRP 2017 from the mid-November date indicated only a few weeks ago by the energy minister.

The unfolding events around the Energy Indaba mooted by the DoE for early December 2017, and the pending release of IRP 2017 following “policy adjustment” input by the cabinet, with the possibility of “Forced Nuclear”, could be dramatic. Watch this space!

Here is the full article

New study points to 90% renewables mix being least cost by 2050

Engineering News, Dr Tobias Bischof-Niemz, 15 September, 2017.

ew analysis conducted using updated cost assumptions for solar photovoltaic (PV), onshore wind and batteries shows that the share of renewable energy in an electricity mix that would also be the least cost for South Africacould grow to above 90% by 2050.

Such a portfolio, the study indicates, will be 30% cheaper than the generation mix currently outlined in the Draft Integrated Resource Plan (IRP) Base Case, published by the Department of Energy (DoE) in November 2016.

The analysis represents an update of the least-cost mix presented in March by the Council for Scientific and Industrial Research (CSIR) in response to the DoE’s call for public comment on the IRP Base Case.

In the March response document, the science council argued that the least-cost mix to meet a projected 2050 demand of 522 TWh would comprise more than 70% renewables, with the balance of the energy arising from coalgas and hydro. Such a mix was calculated to be R75-billion a year cheaper than the one proposed in the Base Case and included no nuclear, which made up 28% in the Base Case.

(Ed. note: What will prevail in our energy decisions – corruption and vested interests, or common sense?).

Here is the full article.