Observing the world of renewable energy and sustainable living

Archive for the month “January, 2018”

De Prijs van een Warmtepomp

[source] Lucht-water warmtepomp

Type warmtepomp Gemiddelde kostprijs [euro]
grond-water 10-25k
water-water 15k +
lucht-lucht 4-7k
lucht-water 4-7k
hybride 5-7k

[] – Kosten Warmtepomp
[] – Alpha Innotec SW-42 warmtepomp, 4 kW (7.345,- incl BTW)

Ground Drilling Vertical Heat Exchanger for Heat Pump

Realistic price calculation:

Freestanding house: 750 m3
Two-three drilled wells of 85 meter each in the garden, 6 meter apart
Temperature cold side: 12 degrees centigrade
Project size: two men, one day
Energy saving: up to 70%

[] – Average price tag:

Average residence, 8 kW heat loss and average geology, boiler 300 liter en floor heating 160 m2
Average space heating cost with natural gas for Dutch house-hold: 1,000 euro.

All-in prices for single household:

Soil-water heat pump with vertical heat exchangers: 20000 € excl. VAT
Soil-water heat pump with horizontal heat exchangers: 17000 € excl. VAT
Air-water heat pump: 14000 € excl. VAT
Subsidy: 1600 euro in 2018

Prices likely come down if you increase project scale. New homes will have no choice as proposed new regulation will forbid a natural gas connection for new-build homes. For the typical Dutch terraced houses, investment costs are lower.

[] – In the Netherlands there are 7 million households. Of these 160,000 do own a heat pump. Currently this number increases with 20,000 per year. As per 2021 this number will increase as all new buildings by then will be deprived of a connection to the existing natural gas grid.

New Approach Pumped Hydro Storage

A company from Stuttgart, Germany proposes a new way of thinking about hydro storage. The design entails a giant cylinder with a stone piston sawn out of rock. During times with excess renewable energy the piston is lifted by water pressure from underneath. The potential energy can be retrieved by letting the piston sink again, propelling turbines.

A first pilot of 30 m deep and 20 m diameter is to be build in Saudi-Arabia, but no financial means have been allocated so far. Paperware so far.

[] – Company site
[] – Tüftler machen Gefällekraftwerk ohne Gefälle möglich

Photocatalytic Water Splitting

New TiO2 photocatalyst for water splitting. H2 bubbles are generated from the catalyst surface only by sunlight irradiation. Chemistry department of NUS.

[] – Photocatalytic water splitting

Solar driven water splitting for large-scale hydrogen fuel production from semiconductor photo-electrodes has the potential to provide energy on large scale from renewable, sustainable sources. Our research focuses on the kinetically more demanding oxygen-evolution reaction, and we prepare thin film metal oxide photoanodes by low-temperature, solution-based processes. One promising light absorber is TiO2:(Nb,N) where Nb and N substitute for Ti and O on their respective lattice sites in anatase. These materials are prepared by sol-gel processing followed by annealing in flowing ammonia. We observe a band-gap energy as low as 2.0 eV at 25% Nb and 2% N. In conjunction with a RuO2 catalyst, powdered TiO2:(Nb,N) evolves O2. A second class of materials we study is the transition-metal tungstates, and we have prepared our most promising candidate, CuWO4, by several routes: electrochemical deposition, sol-gel processing, and spray pyrolysis. These methods afford highly reproducible and robust CuWO4 thin-film electrodes on transparent conducting substrates. CuWO4 is an n–type semiconductor with a band-gap energy of ~2.4 eV. CuWO4 thin films photooxidize water with simulated solar radiation with a nearly quantitative Faradaic efficiency for O2 evolution at no applied bias in the presence of the sacrificial electron acceptor, [Fe(CN)6]3–. Most important, these thin-film electrodes are stable against photocorrosion when illuminated with visible light at neutral pH, a significant improvement to the more commonly studied photoanode, WO3. Current efforts are aimed at preparing complex tungstates that absorb lower energy light to improve the quantum yield. This talk was presented on May 14, 2013 as part of the IHS Markit Seminar Series.
Bart Bartlett, Department of Chemistry, University of Michigan

Thermal Solar Wood Chips Drying

Total collector size: 348 m2, used to dry 4,000 m3 wood chips per year.

Note how thin the collector really is

[] – Hackschnitzeltrocknung

Solar Road in China

[] – China Opens 1-Kilometer Long Solar Road

Kijkje in een Windmolen

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