Climate Change and Federal Hydropower
A report on the projected effects of climate change on federal hydropower through the end of the twenty-first century.
PNNL’s Alison Colotelo Joins Hydropower Foundation Board
Alison Colotelo, senior research scientist and project manager, has been selected for the Hydropower Foundation advisory board.
The World’s Energy Storage Powerhouse
Pumped-storage hydropower offers the most cost-effective storage option for shifting large volumes of energy. A PNNL-led team wrote a report comparing cost and performance factors for 10 storage technologies.
Device, Method and System for Improving Electrical Power factor and Harmonic Power Quality Through Active Control of Power Quality Improving Electrical Appliances
This patent teaches “power quality-improving appliances” (hereafter referred to as “PQI appliances™”), which are appliances that will counteract the aggregate power factor and harmonic pollution currents within a building to greatly reduce a building’s relative aggregate reactive power and harmonic pollution currents. The PQI appliances simultaneously serve their primary functions as water heaters, space heaters, thermoelectric heating or cooling, range top and oven cooking, for examples. The PQI appliance is therefore a novel application for mundane existing appliance types to improve distribution power system quality.
Adding Batteries to Hydropower Facilities Could Increase Dam Lifespan, Potential Revenue
A modeling study shows that adding batteries to a dam could decrease the wear and tear on hydropower turbines and open up new opportunities for dam operators to earn revenue.
Major Eco-Sensitive Rivers Could See Substantial Hydropower Expansion in a Growing and Transitioning Energy System
Hydropower could expand substantially during the 21st century in many regions of the world to meet rising or changing energy demands. However, this expansion might harm river ecosystems.
TRANSFORMER POWER MANAGEMENT CONTROLLERS AND TRANSFORMER POWER MANAGEMENT METHODS
This method to use controllable loads (e.g., PEV charging rates) to determine the distribution transformer loading condition is unique. The process to calculate the distribution transformer load condition is described in the following steps: (1) Identify the transformer's full load core loss value (watts); (2) Identify the transformer's base load (e.g., 25kVA) and secondary voltage (e.g. 240VAC); (3) use the following equation representing the classical relationships between power, current and impedance (e.g., Power = Current2 * Impedance) to calculate the full load transformer impedance; Transformer Power = Impedance * [Nameplate Power (W) ]2 / [Nameplate Secondary Voltage (VAC)]2 (4) use the transformer base current and calculated full load impedance to determine the maximum transformer voltage drop before exceeding the transformer power limit; (5) implement a periodic A.C. line voltage measurement and control capability (e.g., 240VAC) that records the line voltage and minimizes the PEV charging rate during relative high A.C. voltage times to determine a second A.C. line voltage value; (6) the two A.C. voltage and power values are then used to calculate a no-load transformer voltage. This no-load A.C. voltage estimate can be used to verify transformer voltage remains above its minimum voltage and determine the transformer's current loading; (7) these controls take into account variations in no-load line voltage and can be as simple as a short-term (e.g., ~one-hour) history of the highest line voltage as most residential loads cycle within that time period.
Impacts of Long-Term Temperature Changes on Electricity Investments
Improving the power sector detail in a multisector model shows a 3-22% increase in needed capital investments across the U.S. driven by future peak temperatures.